The utility model discloses a program -controlled constant -current source circuit, including power module, singlechip, programme -controlled varistor ware, controllable steady voltage source and voltage -controlled constant current source module, wherein, the singlechip is connected with the communication of programme -controlled varistor ware, programme -controlled varistor ware output links to each other with controllable steady voltage source input, controllable steady voltage source follower end with voltage -controlled constant current source module input links to each other, through the constant current source of high accuracy is stabilized in the output of voltage -controlled constant current source module. This program -controlled constant -current source circuit output current has the precision height, receives advantages such as temperature is little, programme -controlled adjustable.