Mapping and path estimation is one of the important research areas of robotics. This paper proposes a path estimation method for a given area using swarm robots with dead reckoning sensors. Since a dead reckoning sensor has cumulative errors, the performance of path estimation based on conventional dead reckoning is very limited. This paper utilizes swarm robots and proposes data processing techniques to improve the performance of path estimation. The simulation results demonstrate the feasibility of the proposed method.