Provided is a solid-state imaging unit that includes a stacked structure including a sensor substrate and a circuit board. The sensor board has an effective pixel region where an imaging device is disposed. The imaging device includes a plurality of pixels and is configured to receive external light in each of the pixels to generate a pixel signal. The circuit board includes a chip including a first portion and a second portion that are integrated with each other. The first portion includes a signal processing circuit that performs signal processing of the pixel signal. The second portion is disposed at a position different from a position of the first portion in an in-plane direction. Here, both the first portion and the second portion are disposed to overlap the effective pixel region in a stacking direction of the sensor board and the circuit board.