To provide a valve timing adjusting device improving productivity and inhibiting drop of durability and generation of abnormal noise.

A device is provided with an electric motor including a rotary shaft body 7 provided with a pair of connecting projection part 76 projecting in a radial direction opposite side and generating controlled torque of output from the rotary shaft body 7, and a phase adjusting mechanism including a planetary carrier 40 provided with a pair of connecting structures 90 connected to each connecting projection part 76 and rotating a one unit with the rotary shaft body 7 and adjusting relative phase between a crankshaft and a camshaft according to controlled torque of input to the planetary carrier 40 from the rotary shaft body 7. Each connecting structure 90 includes a pair of fitting parts 94 formed harder than a tubular main body member 80 of the rotary shaft body 7 and fixed in an inner circumference side of the main body member 80 to be in roughly parallel with a radial direction of the main body member 80. Each connecting projection part 76 is connected to the rotary shaft body 7 by being fitted between the pair of the fitting part 94 of the corresponding connecting structure 90.