The male Spanish counterpart of quinceañera is quinceañero.
Quinceañera is the feminine form used for a girl or young woman celebrating her fifteenth birthday and the associated rite of passage. Quinceañero is the masculine form, used for a boy or young man marking the same age milestone.
The celebration is most strongly associated with girls, so quinceañera is much more familiar internationally. However, boys may also have celebrations at fifteen, and Spanish-language usage can describe the celebrant as a quinceañero.
The ending changes according to grammatical gender: -a is feminine and -o is masculine. This differs from quince años, which simply means “fifteen years” and does not identify the celebrant’s gender.