The invention relates to a digital impedance adaptive laser diode driver and belongs to the technical field of electronic equipment. The driver mainly comprises a single chip microcomputer (1), a digital to analog conversion module (2), a power output module (3), a load judging module (4), a delay compensation module (5), a voltage tracking module (6), and a power-off protection module (8). The driver can actively adapt to the change of the load during work, and has the advantages of high efficiency, wide load adaptation range, high safety and high reliability.