As a motor is rotationally driven, a valve stem is reciprocally displaced to open or close a flow passage formed in a housing for a high temperature fluid. The motor is held via a bracket where inner surface is concavely recessed contour, and the bracket has a predetermined height and a plurality of openings are formed on the wall surface of the bracket. The housing and the bracket are made integral with each other, and supporting portions formed between adjacent openings are dimensioned to have a smallest cross sectional size necessary from the viewpoint of a strength. With this construction, an efficiency for performing an assembling operation for a motor driven type flow rate controlling valve can be improved, and moreover, a quantity of heat to be conducted from the bracket to the motor side can be reduced.