In this paper it is studied on the fluctuation of various life risks with the passage of time and is presented the coefficient of the fluctuation ; a which represents the fluctuation of life risks. Furthermore, it is studied on the relation between the results of these analyses and the results of inquiries about loss of lives and risky level of each death. It was made clear with these studies; (1) Risk perception to the life risk has same tendency both to accidents and disasters and to deseases. The smaller people estimate the number of deaths by a cause, the safer people feel its cause of death both in the accidents and disasters and in the deseases, and (2) In the relation between a and the risk perception, there is a positive correlation at the accidents and is a negative correlation at the deseases. People feel the cause of death is more dangerous while the life risk decreases in the accidents. In contrast with this the safer people feel, the life risk is on the decrease in the deseases.
