The attitude control problem of a satellite using small thrusters was investigated. With a simulation example, the drawbacks of control method using slantwise on-off switching line proposed in the relevant reference were discussed. A necessary and sufficient condition for an ideal limit circle was deduced theoretically in the case that the desired attitude precision and the parameters of thrusters and slantwise on-off switching line were known previously. Analysis on the case that the ideal limit circle cannot be formed was also conducted. Based on these analyses, a new control method called "Modified Limit Circle Control" was proposed as well as its design procedure. This study can provide meaningful reference for some relevant engineering applications.