Belcastro is an Italian surname. Notable people with the surname include:
James Belcastro (1895–1945), American mobster Lisa Belcastro (born 1988), American politician Luca Belcastro (born 1964), Italian classical composer Marie Belcastro (1920–2015), American murder victim Pete Belcastro, American television and radio personality Sarah-Marie Belcastro (born 1970), American mathematician known for mathematical knitting