The collision between satellites IRIDIUM 33 and COSMOS 2251 indicated that the clash of two on-orbit satellites was becoming an inevitable reality. Our calculation with the two-line orbit element by NORAD showed that some two geostationary satellites had approached very close in July 2009. Therefore, more attention should be given to avoid such collisions. This paper analyzes the orbital long-term variation of a dead satellite drifting in the geostationary orbit. Also, the negative effects posed by dead satellites upon the on-orbit operational geostationary satellites are studied. Then the paper proposes a novel idea to launch a satellite sweeper whose purpose is to collect the on-orbit dead satellites and help them de-orbit to a "graveyard". The satellite sweeper consists of a parent satellite and a child satellite. The child satellite collects a dead satellite and transfers it to a higher orbit. The parent satellite stationed in the geostationary orbit is in charge of refueling the child satellite. The strategy of maneuver and rendezvous is presented and a series of formulas are derived. The analysis results show that our method to clean the geostationary orbital zone is practical and fuel-saving. With the help of just a few satellite sweepers, we can gain a clean environment of geostationary orbit environment again. satellite sweeper, geostationary orbit, dead satellite, de-orbit, rendezvous Citation:Li Y H, Yang K Z, Shan C S, et al. A preliminary study on dead geostationary satellite removal.