Júlio Dinis, pseudonym of Joaquim Guilherme Gomes Coelho (14 November 1839 – 12 September 1871) was a Portuguese medical doctor and poet, playwright and novelist.

His novels, extremely popular in his lifetime and still widely read in Portugal today, are written in a simple and direct style accessible to a large public.

Retiring to the coastal town of Ovar for his health, he wrote the novel for which he is best known, As Pupilas do Senhor Reitor (1867; "The Dean's Pupils"), depicting country life and scenery in a simple and appealing style.

Júlio Dinis died at the young age of 31 of tuberculosis, and some of his works including his poems and plays were published posthumously.

A translation of Uma Família Inglesa by Margaret Jull Costa was published in 2020,[1] the first of his works to be available in English.