Simon Marrero is one of four brothers from a New Orleans jazz family dynasty. Father Billy Marrero was a bassist who was among the first half-dozen instrumentalists to figure out that his instrument could be plucked as well as bowed. He tried to turn his entire brood into bassmen, but sons Laurence Marrero and John Marrero rebelled by taking up banjo. Simon Marrero was the senior sibling on the low axe, serving as a teacher to younger brother Eddie Marrero. The latter variation on "Simon Says" did not occupy all his waking time, even factoring in lessons for other bassists such as Al Morgan. Simon Marrero had time for a recording career that rivaled that of brother Laurence, usually considered the most famous musician in the family.
The bassist cut sides with bandleaders such as Papa Oscar Celestin and Dave Nelson; one amusing variation in discographies concerns just what type of bass instrument was being played. Some researchers insist the man only recorded on the strange brass bass, a version of the contrabass made out of metal that fares quite well in situations such as a drunk trying to kick the face of the instrument in. The presence of this instrument may explain why he is sometimes credited with playing tuba on recordings. The gumbo of instrumental interpretations has an attractive aroma whatever the final decision; by the standards of most music, a bassist who sounds like a tuba or the other way around is a good thing. This Marrero had no shortage of gigs whenever fellow musicians got a chance to hear him play bass, brass bass, or tuba. During one period of his career he worked with the Blue Rhythm Band in New York City. He also played in New Orleans with the Original Tuxedo Jazz Orchestra.