Disclosed is an environmentally friendly near-azeotropic mixed refrigerant, consisting essentially of HFO-1234 yf, HFE-143a and a third component, with the mass percentage of each component being: 70%-98% of HFO-1234yf, 1%-15% of HFE-143a and 1%-15% of the third component. The refrigerant of the present invention is environmentally friendly, excellent in thermodynamic properties, can directly realize drop-in substitution in an original system using HFC-134a without changing any parts, and can be used as a long term alternative to HFC-134a.