The utility model discloses a spraying system in heading machine, which comprises a housin, end cover and main shaft, end cover fixed mounting is at the casing left end, axial installation is followed on the casing to the main shaft, the main shaft left end passes casing and end cover, the main shaft all rotates with casing and end cover to be connected, be equipped with the water seal body between main shaft right part and the casing, the water seal body links firmly with the casing, the water seal body rotates with the main shaft to be connected, the casing right part is equipped with first water course, be equipped with the second water course on the water seal body, be equipped with the third water course along the axial on the main shaft, shell backend is equipped with the water inlet, water inlet and first water course access connection, export of first water course and second water course access connection, the export of second water course is intake to hold with the third water course and is connected, the third water course goes out the water end (W. E. ) and is equipped with the delivery port. The utility model has the advantages of simple structure and reasonable design and simple to operate comes a ring damage, outlet to block up or the not hard up problem that will cause the profit to mix of technology plug in case can solve current interior water -spraying system check, and water oil separating is effectual, intakes, the drainage convenience.