A bonding type crystal controlled oscillator includes a crystal package and a circuit package bonded by two-tier bonding. An anisotropy conductive adhesive is interposed between back surface of the crystal package facing the circuit package and an upper surface of the circuit package facing the crystal package. The anisotropy conductive adhesive includes a thermosetting resin containing solder micro particles dispersed in the thermosetting resin. Assuming that a thickness of the output terminal formed at the crystal package is C μm, a thickness of the external terminal formed at the circuit package is D μm, and an average outside diameter of the solder micro particles dispersed in the anisotropy conductive adhesive is E μm, the dimensional relation is set to (C+D)>E.