In order to improve the stability and economy of the multi axis servo drive system for air conditioning condenser bending machine,an interface circuit design scheme based on field programmable gate array (FPGA) was proposed for the multi axis servo drive system.A pulse multimode transmission interface circuit supporting up to 8 axes was implemented by using FPGA.It could be used to adapt to the servo driver and upgrade the original CNC system of air conditioning condenser bending machine.Using Verilog HDL language and integrated development environment of Quartus prim,the FPGA interface circuit was tested with Intel Cyclone10LP.The experimental results show that the interface circuit can stably output,meeting the requirements of multi axis CNC system of air conditioning condenser bending machine.