Santiago Polanco-Abreu (October 30, 1920 – January 18, 1988) was the 10th Resident Commissioner of Puerto Rico.

He was one of the founders of the Institute for Democratic Studies in San José, Costa Rica.

Polanco-Abreu was elected as a Popular Democrat to be Resident Commissioner of Puerto Rico to the United States Congress, November 3, 1964, for the term ending January 3, 1969.

He was a resident of San Juan, Puerto Rico, until his death there on January 18, 1988.

This article incorporates public domain material from the Biographical Directory of the United States Congress