Porter had been suffering from breast cancer for four years before her death, but "many thought she was winning the battle," according to journalist Matt Buchanan.[3] In the last three weeks of her life, she became very sick and was admitted to hospital, where she was in intensive care for the final 10 days. She died aged 54 on 10 December 2008.[3]
On 21 February 2010, actress Cate Blanchett read excerpts from Porter's posthumously published short work on literary criticism and emotions in literature, On Passion, at the Malthouse Theatre, Melbourne.[6]
Brett Dean dedicated the first movement of his "Epitaph for string quintet (viola quintet) (2010)" in memory of Dorothy Porter.
