A nozzle adapter for a Presta valve contains: a connection seat, at least one control element, at least one returning element, a seal cover, and a controlling means. The connection seat includes an imaginary axis line, an inlet, an outlet, an air stop ring, a conduit, an engagement position, a coupling slot, and a stopping means. A respective control element has a fixing shaft, an engaging portion, and a controlled portion. The at least one returning element is arranged on the at least one control element. The seal cover is fixed outside the coupling slot, and an airtight space is defined in the coupling slot. The controlling means mounted on a center of the connection seat opposite to the inlet and in the conduit of the airtight space to move with the controlled portion.