Abstract: The working principle and performance of VAS sliver rejecting system were introduced.Comparing VAS (or traditional tower type separator)in primary processing line with pneumatic stem separator system in PROTOS 70 cigarette maker, it was found that the sliver could be effectively rejected from cut tobacco by optimizing and adjusting the separator system of PROTOS 70, its content in cigarette was below specified limit, and it was feasible to save the sliver rejecting equipment in primary processing line.