Diego Modrušan (born 2 September 1980) is a Croatian professional handball player.

He won two Croatian Championships with Zagreb and the Italian Serie A with Handball Casarano.

In 2000 he signed with RK Zagreb, where he won two consecutive titles and made his debut in the EHF Champions League.

In 2007 came the call of Italian champion Casarano, which made another important acquisition with Modrušan after Vito Fovio the year before.

In 2008 he was called up by the Italian university team to compete in the world championship held in Oderzo and Meolo.