Ron: "Seamus reckons that Harry's lying about You-Know-Who."
Hermione: "Yes, Lavender thinks so too..."
Harry: "Been having a nice little chat with her about whether or not I'm a lying, attention-seeking prat, have you?"
Hermione: "No, I told her to keep her big fat mouth shut about you, actually. And it would be quite nice if you stopped jumping down Ron and my throats, Harry, because if you haven't noticed, we're on your side."
— Hermione, Harry, and Ron talking about forming the D.A.

Following the death of Cedric Diggory, the Ministry of Magic refused to accept Harry and Dumbledore's claims that Lord Voldemort had returned, and the Daily Prophet labelled them either liars or nutters. However, Hermione and Ron believed Harry and defended him against the criticism of doubtful classmates. Though occasionally Harry vented his frustration at them, Hermione and Ron stuck by him. They also wanted to become members of the reconvened Order of the Phoenix but were not allowed to because they were under-age. Hermione helped exterminate 12 Grimmauld Place, which served as headquarters for the Order, and was immensely relieved when Harry was acquitted of the charge of having used under-age magic. Also before returning to Hogwarts, she and Ron learned that they had been appointed prefects for Gryffindor house and received badges. She took her position very seriously.

Once the school year began, Hermione resumed some of her activism on behalf of house-elves, though she was not as intense about S.P.E.W. as she had been the previous year. She learnt how to knit socks and hats for the house-elves and hid them in Gryffindor Tower. The elves found this attempt at freeing them insulting, and they stopped cleaning the Tower at all. Dobby, already a free elf, was the only one who enjoyed the gifts. He took everything Hermione had made and cleaned the Tower by himself, a fact which Hermione did not know.

Hermione: "She's an awful woman. Awful. You know, I was just saying to Ron when you came in ... we've got to do something about her."
Ron: "I suggested poison."
— Hermione and Ron on Professor Umbridge

Meanwhile, it was not long before Hermione realised that the Ministry of Magic had decided to interfere at Hogwarts. Dolores Umbridge, a cruel, falsey sweet Ministry employee with a personality like "poisoned honey", was appointed as the new professor of Defence Against the Dark Arts. She refused to teach students practical
only on theory. With this being the case, Hermione decided that Hogwarts needed a competent teacher and, together with Harry and Ron, founded Dumbledore's Army, a secret organisation in which students would gather after classes and be taught practical defensive spells. She suggested that Harry be the teacher; though he originally thought the idea ridiculous, he consented to teach the class. One of the many spells Hermione learned was the Patronus Charm; hers took the form of an otter. Hermione also became one of the few people brave enough to call Voldemort by his actual name. However, Hermione made the mistake of arranging the first meeting to take place in the Hog's Head, as opposed to the Three Broomsticks, which Sirius, appearing in the Gryffindor Common Room fire, would've made it a lot more harder for anyone to overhear. Willy Widdershins, who was in the Hog's Head, went to Umbridge, who instituted Educational Decree Number Twenty-Four to forbid any type of students groups from being formed.

Halfway through the year at Hogwarts, Harry had a vision- a real vision, which was a snake (Nagini, Voldemort's snake) biting Mr Weasley during his task in the Order of the Phoenix. Mr Weasley was carried into St. Mungo's Hospital, where he was screamed at from Mrs Weasley, having said that he ought to try stitching his wound instead of healing it with magic. Hermione was one of the few who visited him and stayed at Number Twelve, Grimmauld Place for a couple of weeks until Mr Weasley was nursed back to health. Hermione had managed to convince her parents by telling them that skiing wasn't really her thing and that people who were serious about exams (Ordinary Wizarding Levels, O.W.L.s for short) stayed at Hogwarts and studied.

The D.A. brought Harry into greater contact with Cho Chang. After a meeting, Harry kissed Cho, and when he didn't tell it to Hermione and Ron, she guessed, asking if Cho had cornered him after the meeting. She explained to Harry and Ron that Cho was having a hard time since Cedric Diggory, who she used to go out with, died. Hermione gave Harry advice on Cho and girls in general. In an effort to combat the lies being told about Harry, Hermione also arranged for an interview during a Hogsmeade visit with Rita Skeeter to be printed in The Quibbler telling his side of the story. Despite being banned, it became the magazine's best-selling issue of all time.


Hermione: "It's sort of exciting, isn't it? Breaking the rules!"
Ron: "Who are you and what have you done with Hermione Granger?"
— Hermione and Ron

It was Hermione's brilliant spell-work that ensured the security of Dumbledore's Army. She created coins enchanted with the Protean Charm, an advanced spell, as a method of communication, and jinxed the club's attendance sheet to give any tattler a horrendous rash on the face, which would spell out "SNEAK" in painful boils. This is exactly what happened to Marietta Edgecombe later in the year when she betrayed the D.A. to Umbridge. When Harry learned that they could not find a counter curse, he swelled with pride at Hermione's jinxing ability. Hermione was not exposed at that time, but later she was brought to Umbridge's office by the Inquisitorial Squad.

Late in the fall of that year, Hagrid, who had been missing for the entirety of the school year, returned to Hogwarts. Hermione, Harry, and Ron ventured down to see him immediately even though it was after curfew. Hermione was aghast at the injuries Hagrid had sustained and greatly curious as to his story. She was almost caught when Umbridge called on Hagrid that night. Months later, Hermione and Harry learned why Hagrid was perpetually bruised and cut. He had brought his half giant brother Grawp back from the giants.Just after their class took their O.W.L.s, Harry had a vision of his godfather being tortured by Voldemort in the Department of Mysteries. Hermione was worried that it was a trap and convinced Harry to try to contact Sirius before doing anything rash. To that end, she accompanied Harry in an act of solidarity as he sneaked into Umbridge's office to use the Floo Network, with the assistance of Ron, Ginny Weasley, and Luna Lovegood, but they were ultimately caught. When Umbridge threatened to use the Cruciatus Curse on Harry during questioning, Hermione interceded, coming up with a lie that she and her fellow D.A. members had been building a weapon for Dumbledore.


She successfully lured Umbridge into the Forbidden Forest, where Umbridge was carried away by a herd of centaurs. Hermione had predicted that the centaurs would let her and Harry go, since they did not insult the centaurs and were young enough to be considered "foals." However, the centaurs were already enraged by Umbridge and were further angered when Hermione admitted that she had hoped that they would drive Umbridge off, being insulted that they were thought of to do the bidding of humans. They were about to carry the two students off as well, but Grawp stumbled onto the scene and a fight broke out between the giant and the herd. This allowed Hermione and Harry to escape and meet up with Ron, Ginny, Luna, and Neville, who had escaped from the Inquisitorial Squad. The six students flew on Thestrals to the Ministry of Magic to try to save Sirius.

Hermione's fear turned out to be justified, as Harry's vision was a ruse designed to lure him to the Ministry to obtain a prophecy Voldemort sought. As soon as Harry did this, the six D.A. members were surrounded by Death Eaters, and a battle ensued. Hermione stunned Nott when he grabbed Harry, thus freeing him and causing Nott to be injured by the collapsing shelves of prophecies. She later stunned another Death Eater and silenced Antonin Dolohov before he could alert the other Death Eaters to the group's location. She was critically injured by the curse Dolohov subsequently struck her with, but made a full recovery.

Hermione: "Well, it's certainly given them lots to write about. And that interview with Harry isn't exclusive, it's the one that was in The Quibbler months ago..."
Luna: "Daddy sold it to them. He got a very good price for it, too, so we're going to go on an expedition to Sweden this summer to see if we can catch a Crumple-Horned Snorkack."
Hermione: "That sounds lovely."
— Hermione and Luna

Hermione was challenged in more ways than one that year when she met Luna Lovegood, whose belief in many things without logical grounds baffled Hermione. However, the two became friends after accepting one another's differences.