The utility model provides a cold sediment machine and seal structure thereof, wherein, the seal structure of cold sediment machine sets up in the cylinder of cold sediment machine and the junction ofadvancing the sediment barrel, and seal structure includes: first sealing member sets up on advancing the sediment barrel, and first sealing member includes first sealing ring, and the first end of first sealing ring is connected on advancing the sediment barrel, the second sealing member sets up on the end cover of cylinder, and the second sealing member includes the second sealing ring, and the2nd seal annular sleeved establishes outside first sealing ring, has the predetermined distance between the first end of the free end of second sealing ring and first sealing ring on the axial direction of edge second sealing ring. The technical scheme of the utility model the problem that the quick -witted sealing mechanism of the cold sediment among the prior art leaks the sediment has easily been solved effectively.