Together with fellow Death Eaters, he arrived at Hogwarts through the vanishing cabinet. There, he fought in the Battle of the Astronomy Tower, where he fired killing curses at random, thereby accidentally killing fellow Death Eater Gibbon. After the death of Albus Dumbledore through Severus Snape, the Death Eaters fled, heading towards the borders of the Hogwarts grounds to disapparate. On the way, he shot an ignition curse at Rubeus Hagrid's cabin and burned it down. When Harry, determined to stop Snape followed them, Rowle fired the Cruciatus Corse at Harry but was stopped by Snape who claimed that Potter belonged to Voldemort. Rowle then disapparated from Hogwarts.
In 1997, he tracked Harry Potter, Ron Weasley, and Hermione Granger to Tottenham Court Road along with Antonin Dolohov, but the two Death Eaters were defeated and their memories were modified by Hermione to cover their escape. After this failure, Rowle and Dolohov were punished by Voldemort, who ordered Draco Malfoy to torture both with the Cruciatus curse.
He also fought at the Battle of Hogwarts. His fate after the battle and Voldemort's final defeat, however, is uncertain. Though, he is most likely to have been sent to Azkaban for his crimes.