The invention discloses a technology for extracting arachidonic acid oil by an aqueous enzymatic extraction. The technology comprises the following steps: using Mortierella alpina as an original strain, fermenting and culturing, diluting by adding distilled water to obtain a thallus suspension, regulating the pH value of the suspension, adding a biological enzyme, oscillating at constant temperature for 6-10 hours, adding ethanol and normal hexane to carry out oil extraction, centrifugating to delaminate, taking out an organic solvent phase, adding normal hexane into the left water phase and solid phase to carry out secondary extraction, centrifugating to delaminate, combining with the organic solvent phase, and carrying out rotary evaporation on the organic solvent phase to obtain the oil and an organic solvent. The invention has the advantages of low energy consumption, low cost, high yield of arachidonic acid oil, high quality, simple reactor, easy batch large-scale application and the like.