The utility model relates to the field of oil-gas equipment. According to the oil tank sealing cover structure, safe oiling can be achieved without taking down an oil gun. The oil tank cover comprisesan oil tank cover central pipe and a sealing cover shell provided with an oil gun inlet pipeline, a rear cover plate structure is arranged in the sealing cover shell, the oil tank cover central pipepenetrates through the rear cover plate structure and is communicated with the oil gun inlet pipeline, and a sealing structure is arranged in a gap between the rear cover plate structure and the oil tank cover central pipe. According to the utility model, even if the oil gun is not pulled out, the situations of oil gas and oil liquid leakage are avoided, so that potential safety hazards such as fire and explosion are avoided. And meanwhile, dust in external air cannot enter the oil tank, and oil products cannot be polluted. The utility model is particularly suitable for occasions requiring frequent oil supply and refueling operations.