Oscar was born on August 24,1951in New York City. His family was Cuban American and grew up in the Spanish Harlem. As a child the family's income depended on the father's job as a cook as a child Oscar was diagnosed with a kidney infection and was hospitalized for 1 year. After graduating high school he had jobs until he headed off to college .He enrolled in the city college of New York. There he earned a bachelors in English literature. Then continued to get a masters in creative writing in 1976.He had a job in a small press, writing news blobs and signs. That published his first book Our House in the Last World. His writing style is about Cuban Americans find their way in America. He had two wives the first one he divorced and then met Lori Marie Carlson. He and Lori worked on translating a book of Cuban poems.
The first book he published was Our House in the Last World .This book won the Rome Award. This allowed Oscar to go to Rome for a year and study writing. The next book was the Mambo Kings Plays Songs of Love this book was published while he was in Rome in 1989. The Mambo Kings Plays Songs of Love won the Pulitzer Prize in 1993.
Oscar died on October 13, 2013 in New York, New York. He was playing tennis and had heart attack .He never regained consciousness He was 62 years old.