The utility model relates to a lubricating oil sealing device for a turbogenerator stand type bearing. A turbine end bearing smoke discharge pipeline is led out from a turbine end bearing seat of the generator; an exciter end bearing smoke discharge pipeline is led out from an exciter end bearing seat; the turbine end bearing smoke discharge pipeline and the exciter end bearing smoke discharge pipeline are respectively connected with independent smoke discharge fans; a turbine end oil discharge pipeline is arranged at the lowest point of the turbine end bearing smoke discharge pipeline; an exciter end oil discharge pipeline is arranged at the lowest point of the exciter end bearing smoke discharge pipeline; the turbine end oil discharge pipeline and the exciter end oil discharge pipeline are respectively connected with an oil return pipeline; and the oil return pipeline is communicated with a main oil tank. In the utility model, the negative pressure outside a bearing air seal ring is effectively reduced, and the air pressure inside and outside a bearing box is balanced, thereby realizing no spillover of the oil fog in the bearing box.