The utility model relates to the field of electronic circuit, and discloses a charging circuit of a digital display caliper. The charging circuit comprises a power management chip, wherein the power management chip comprises a positive voltage input end, a state indicating end, a current setting monitoring end, and a battery connecting end; the positive voltage input end is connected with an external power supply; a first branch and a second branch are connected in parallel between the positive voltage input end and the state indicating end; the first branch comprises a red LED and a first resistor connected in series with the red LED; the second branch comprises a green LED, and a second resistor, a triode and a third resistor which are connected in series with the green LED; the current setting monitoring end is connected with a fourth resistor; and the battery connecting end is connected with a positive electrode of a battery. By adopting the charging circuit of the digital display caliper, the charging of the lithium battery can be realized by connecting a simple peripheral circuit to the power management chip externally, the loss of the lithium battery is low, and the occupied spatial volume of the circuit is reduced.