Alex Correia Diniz (born 20 October 1985) is a Brazilian professional racing cyclist. He was born in Recife, and his specialties are climbing and endurance races.

He served a two-year drugs ban between 2009 and 2011, after testing positive for erythropoietin (EPO) and his 2009 results were cancelled. In 2013, racing for Funvic Brasilinvest–São José dos Campos, Diniz won the queen stage of the Tour de San Luis. He soloed to victory after attacking at the foot of the final climb, the Mirador del Potrero, taking the leader's jersey in the process.

In 2017, Diniz was given an eight-year ban for anomalies in his biological passport.