An embedded tube include a straight body, a mounting tube positioned below the straight tube body and a mounting sleeve sleeved on the outside of the straight tube body and the mounting tube, the mounting sleeve is a cylinder parallel to the straight pipe body, An upper end thereof is fixedly connected with that middle part of the outer wall of the straight tube, An upper half of that mount tube is sleeved between the straight tube body and the mount sleeve, An annular internal saw tooth with an inverted triangle cross section is arranged on an outer wall of the mounting sleeve below the straight pipe body, An inn wall of the mounting pipe is provided with an outer saw tooth with a triangular cross section corresponding to the inner saw tooth, a mounting cap parallel to the inner wall of the mounting pipe is sleeved on the inner side of the lower part of the mounting pipe, the top end of the mounting cap is fixedly connected with the inner wall of the mounting pipe, and a mounting groove is formed between the mounting cap and the mounting pipe. The invention has the advantages of simple and convenient operation, time-saving and labor-saving, good fixing effect on the lower pipelineand good sealing performance.