Energy-saving oil-gas separator of ground source heat pump

The invention discloses an energy-saving oil-gas separator of a ground source heat pump, and belongs to the field of oil development. The energy-saving oil-gas separator comprises a cylindrical shell, and a first heat preservation layer is nested on the outer side of the shell; a second trapezoidal heat preservation layer is fixed outside the first heat preservation layer, and a third rectangular heat preservation layer is fixed outside the second heat preservation layer. A gas inlet pipe is arranged on the upper end face of the shell, and an exhaust pipe and an oil drain pipe are arranged at the upper end and the lower end of the outer side face of the shell respectively. The multiple heat preservation layers of different heights are arranged outside the shell of the oil-gas separator to preserve heat of the shell so that different heat preservation effects in different positions of the shell can be achieved; due to the fact that the different heat preservation layers are different in height, compared with the scheme of the prior art, the manufacturing cost of the oil-gas separator can be further lowered.