María Martha Serra Lima (born December 19, 1944) is an Argentine singer.
Born in Buenos Aires to a family of auto dealership proprietors, Serra Lima was first signed on to a record label in 1977, and became famous across Latin America and in Spain during the 1970s and 1980s. Known for her contralto vocal texture and her repertoire of love ballads and boleros, she collaborated extensively with singer-songwriters from elsewhere in Latin America, particularly Mexican standards such as Los Panchos and Armando Manzanero; among her best-known, non-Hispanic interpretations is that of Paul Anka's ''My Way''. Her albums became hits in Mexico, Puerto Rico, Chile, Venezuela, and elswhere in the region, apart from her home country.
Serra Lima is well known also for her size: At an estimated weight of about 230 pounds, even she herself has poked fun out of her weight, once declaring "with over 100 kg, I still train like a fifteen year old girl!"
She has shared the stage with numerous major international singers, done multiple international tours and won many awards through her career as a singer.