Abstract: Large scale helium cryo-plant is the necessary support equipment in the fields of cutting-edge scientific research and high-tech application.With the support of the national major scientific research equipment development project,TIPC has successively carried out the research and development of 20 K,4.5 K and 2.0 K large-scale cryo-pants,breaking through the key technologies such as the stability of high-speed helium turbine expanders,the design and manufacture of ultra-low leakage aluminum plate-fin heat exchangers,the design of high-precision oil filtering system,and successfully developed 2 kW@20 K helium cryo-plant,10 kW@20 K helium cryo-plant,40 L/h helium liquefiers,250 W@4.5 K helium cryo-plant,200 W@4.5 K helium cryo-pant,etc.At present,the development of 2.5 kW@4.5K/500 W@2 K helium cryo-plant is close to the end.The cooling capacity of 2.716 kW@4.5 K and 510.6 W@4.5 K have been obtained,the stability test of the system is in progress.In the future,the research and development of several tens of 4.5K class super large cryo-plant will be carried out.