To provide a noninverting amplifier, an optical receiving amplifying element, and an optical pickup element which perform a stable gain switchover even when a multiple-stage gain switchover is required as in an optical pickup for reproducing and recording a BD, a DVD, and a CD.

In a noninverting amplifier where a base ground transistor Q3 is inserted into a collector side of an input-side transistor Q1 of differential transistor pair Q1 and Q2 provided to a differential amplifying circuit, a base is connected to a base of the base ground transistor Q3 and a collector of an NPN transistor Q5 to which the base is connected, an emitter is connected to the base of the base ground transistor Q3, and an NPN transistor Q7 with the collector connected to a power potential (Vcc) is provided. Thus, an amplifying circuit does not function as the differential amplifying circuit in gain switchover, and a disabled state with an output fixed to a potential lower than a reference voltage is prevented.