Disclosed are an I2C transmission circuit and a display device, whereby a technical problem of incorrect writing to an element other than a target element can be solved. The I2C transmission circuit includes a first selection circuit, a second selection circuit, and a selection signal line. An input end of the first selection circuit is connected to a serial clock line, and an input end of the second selection circuit is connected to a serial data line; and the selection signal line is connected to a control end of the first selection circuit and a control end of the second selection circuit.