Marcos Gueiros (born 16 January 1970 in Belém) is a Brazilian racing driver who has competed in the International Formula 3000 series.

This was a successful season resulting in four race wins and a second place in the championship standings.

Gueiros was signed by Edenbridge Racing to drive one of their state-of-the-art Dallara F393's as of the sixth round of the British Formula Three championship.

The following season Gueiros was signed by Super Nova Racing alongside Kenny Bräck.

In the season opener at the Nürburgring Gueiros finished third, behind Jörg Müller and Kenny Bräck.

After a sabbatical of four years the Brazilian driver returned to the track in the Formula 3 Sudamericana in 2000.