During the development of Bohai J Oilfield，because of the high content of microcrystalline wax，the crude oil is more sensitive to temperature and pressure，and easily precipitates and deposits during the production process，which leads to blockages in the wellbore and near-wellbore areas of production wells，and increases in bottom hole pressure，etc. This phenomenon has seriously affected the normal production of oil fields. In response to this problem，the combination of biological enzymes and chemical plugging agents was used to carry out crude oil unplugging technology research，and the compatibility，emulsification， crude oil stripping，viscosity reduction，interfacial activity，dissolution，and reservoir permeability recovery of the compound system was studied. The results showed that the 5% bio-enzyme WZ7/1% chemical unplugging agent LV compound system could reach 42.79% and 92.03% of the scale sample at the reservoir temperature（57 ℃）and 90 ℃，respectively，and the scale sample peeled off，the efficiency being of more than 80%. The viscosity reduction rate of the crude oil was 83%—92%，and the formed oil-water emulsion had higher stability and better emulsification performance. the reservoir permeability recovery physical model experiment indicating that the permeability recovery rate at temperature（57 ℃）was 43.96%，while the permeability recovery rate at 90 ℃ was 74.97%，indicating that the system had a strong ability to remove the plugging of crude oil caused by heavy component deposition in Bohai oilfield.