The rate of death by cancer is higher than any other deseases in Japan. In order to prevent the number of death by cancer from increasing, it is necessary to find a solution as soon as possible. However, nowaday's diagnosis technology has a limitation in cancer detection. Therefore, some kinds of cancer cannot be detected. In addition, diagnosis is done only qualitatively by looking the condition of organs. From above reasons, quantitative cancer hardness measurement system based on palpation has been developed. However, it is difficult to measure the cancer hardness collectly because of force attenuation. Therefore, it is necessary to consider compensation methods. In this paper, friction and force transmission compensator for cancer hardeness measurement system is proposed. Fricton is compensated in real time by a linear square method and force transmission is compensated by a mapping function. The efficiency of the proposal is verified experimentally.