The invention discloses novel oilfield associated gas denitrification equipment and process. The denitrification equipment comprises a liquid-gas separator, a water removal device, a cooler, a gas-liquid separator, a cooling system, a heating furnace, pressure swing adsorption denitrification towers, a vacuum pump, a storage tank and the like. According to the denitrification process, water vapor and C2+ light hydrocarbon in mixed gas are removed at first to avoid pollution to an adsorbent, then pressure swing adsorption denitrification is performed, and enriched product gas has nitrogen content of less than or equal to 3 percent capable of meeting a quality requirement on commercial natural gas, and is used for the fields of civil gas, fine chemicals, compressed natural gas for vehicles, large-sized gas engines or the like.