Óscar Julián Ruiz Acosta (born 1 November 1969 in Villavicencio) is a former Colombian football referee and current referee instructor.

He had been a referee since 1 January 1995, and his international debut was on 12 July 1995 (Paraguay vs. Venezuela).

He was preselected as a referee for the 2010 FIFA World Cup and sent off Yoann Gourcuff in the France vs. South Africa match.

[1] FIFA appointed Ruiz as a referee instructor and member of CONMEBOL's referee assistance program.

This biographical article related to Colombian football is a stub.