The present invention is formed such that, in order to provide a rotary type actuator and a manufacturing method thereof wherein the precision of the attachment of the arms is increased, the dimensional change of the arms does not occur even during operation and grounding is achieved with reliability, grooves 1a which have a width greater than the thickness of arms 2 in a plate shape are formed in the external surface of a holder 1 in a cylindrical shape and one end of an arm 2 is inserted into one of these grooves 1a so as to be placed on the lower surface of the groove 1a, and, the holder 1, the arms 2, the coil 4 and a conductive member 5 in a band shape that makes an electrical connection between the holder 1 and the arms 2 are injection molded with a resin 6 in the above condition so as to be integrally secured to each other.