PROBLEM TO BE SOLVED: To provide a risk monitoring system, a server and a risk monitoring method, capable of finding a user having a risky condition in an early stage and rescuing the user by monitoring the physical condition of the user while taking weather conditions into consideration.SOLUTION: The risk monitoring system 1 includes a weather measuring device 2 and an information terminal 5 carried by each user. Each information terminal 5 transmits the physical activity data and biological information of the user to a server 4. The server 4 includes a weather data acquiring section for acquiring weather data, a physical activity data acquiring section for acquiring the physical activity data, a biological information acquiring section for acquiring the biological information, a physical condition level determining section for determining whether each user is in a risky condition by utilizing the weather data, the physical activity data and the biological information which are acquired, and a risk information generating section for generating the risk information of the user determined to be in a risky condition. The system transmits the risk information to an information terminal 5 carried by at least another user other than the user determined to be in a risky condition.
