Guarini is the name of several people:
- Giovanni Battista Guarini (1538-1612), Italian poet and diplomat
- Anna Guarini, Contessa Trotti, (1563-1598), Italian virtuoso singer of the late Renaissance
- Guarino Guarini (1624-1683), Italian architect and Theatine priest
- Justin Guarini (born 1978), American singer who rose to fame on the television show American Idol