The invention relates to equipment for modular treatment of oil field wastewater. The equipment comprises a wastewater pretreatment unit, a micro interface control unit for performing coagulation, decoloration and oil removing on a micro interface, a sedimentation unit for removing relatively large particle impurities, a sand filter processing unit for retaining fine flocs, an ozone catalytic oxidation unit for removing poisonous and harmful substances, an adsorption processing unit for removing dissolvable organic matters and micro heavy metal ions, a membrane processing unit for further removing the impurities with large particle size and a sludge processing unit for disposing sludge. The specific equipment comprises a chemical feeding system, a micro interface coagulation reaction box, an inclined tube sedimentation box, an intermediate booster pump, a filter, an ozone catalytic oxidation reactor, an activated carbon adsorption device, a membrane processing device, a stacked type sludge water extractor and a matching pipeline and valve control system. By the equipment, corresponding processing unit can be started through the preset pipeline control system according to different destinations of treated wastewater, and modular treatment of different kinds of oil well operation wastewater is realized.