To provide an electronic throttle capable of reducing manufacturing costs by dispensing with a process for improving sealability by separating air retention formed in injecting a sealing material far from a clearance gap between a thread communicated with an accommodating chamber and a screw groove.

An annular recessed groove 61 recessed from an outer face of a side wall portion 51 to an inner peripheral side is disposed in a state of surrounding the circumference of a through hole 55 of a housing 3 in a circumferential direction, thus an air retention 8 formed in injecting a sealing material 7, can be separated far from a spiral clearance gap between a screw groove 56 communicated with the inside (gear chamber) of the housing 3 and a thread 74, and sealability of the spiral clearance gap can be improved. Thus "a process for coating a surface of the thread 74 with a sealing material" to improve the sealability can be eliminated. As the process for improving the sealability becomes unnecessary, manufacturing costs can be reduced.