A robot cleaner for generating accurate travelling records regardless of floor material is provided. The robot cleaner includes a main body, a drive wheel installed on the main body, a drive motor configured to rotate the drive wheel, a travelling sensor configured to detect rotation of the drive wheel, a first optical sensor configured to detect an obstacle located in a moving direction of the main body, a cleaning tool configured to clean a floor, a second optical sensor configured to acquire an image of the floor, and a processor electrically connected to the drive motor, the travelling sensor, the first optical sensor, and the second optical sensor. The processor is configured to control a memory to store a movement record of the main body based on an output of the travelling sensor and an output of the second optical sensor, calculate a distance moved by the main body based on an output of the second optical sensor in response to detection of an obstacle, and control a cleaning tool to clean a floor in the vicinity of the obstacle in response to the distance travelled by the main body that is calculated as being greater than a threshold distance.