Remus was one of the many Order members who answered Neville Longbottom's call to arms on the 1st May, 1998. Harry, Hermione and Ron returned to Hogwarts and Lord Voldemort gathered his army to attack the school in order to capture Harry Potter. He organised and led groups to fight Death Eaters on the school grounds, along with Kingsley Shacklebolt and Arthur Weasley. His wife initially agreed not to participate in the Battle of Hogwarts, instead staying with their infant son, but was ultimately unable to bear leaving her husband to face such danger without her.

She left Teddy with her mother and raced to Hogwarts, where she was informed that Remus was last seen duelling Death Eater Antonin Dolohov. Dolohov murdered Remus, who was no longer in prime fighting condition, due to months of protective and concealment charms in order to keep his wife and son safe from possible attacks. He was murdered in the Main Courtyard during the first half of the battle along with many others, including Tonks, his wife, who was murdered by her aunt Bellatrix Lestrange.