Hugh Denis Macrossan (20 February, 1881–23 June, 1940) was a politician and judge in Queensland, a State of Australia.

Before embarking on his career in politics and the law, he worked as a teacher in Nudgee for three years.

Macrossan obtained a taste for the law when he worked as an associate for Mr Justice Patrick Real of the Supreme Court of Queensland in 1904.

On 12 June 1912, he married Lydia Cremin Hall Woodhouse at St Patrick's Church in Sydney.

That issue went to the High Court of Australia and later to the Privy Council which determined that the appointment of McCawley was valid.

In 1929, Pope Pius XI appointed Macrossan a Knight of St Gregory the Great.

Macrossan had a "tongue of silver and steel" and was noted for his hard work and speedy judgments.

Unfortunately for Macrossan, two ministers heard his remark and wrote a letter of complaint to the local paper protesting at the judge's comments about the institution of marriage.

Macrossan took the letter as being a contempt of court by the ministers as well as the newspaper, and he duly convicted each of them.