A light-emitting element drive circuit capable of controlling the drive current of a light-emitting element in consideration of changes in a threshold value of the light-emitting element. A laser diode 1 emits light in accordance with a bias current Ib of a bias current drive circuit 2 and a light-emitting current Ip of a data current drive circuit 3. A photodiode 4 outputs a monitor current Im that corresponds to the optical output of the laser diode 1. A bias current feedback circuit 8 detects a change in the threshold current in accordance with the current Im, and outputs a control signal CS1. The bias current drive circuit 2 generates a bias current Ib that corresponds to the threshold current Ith of the laser diode 1 after the change. A light-emitting current feedback circuit 9 detects a change in the optical output of the laser diode 1 in accordance with the current Im, and outputs a controls signal CS2. The data current drive circuit 3 generates a light-emitting current Ip relative to a pre-determined optical output of the laser diode 1 in accordance with the control signal CS2.