An operation appropriateness determination system according to an aspect of the present disclosure includes an authentication apparatus that identifies an operator on a basis of a feature of the operator and that outputs information for identifying the operator, a biometric sensing apparatus that obtains biological information regarding the operator and that outputs the biological information, an operation sensing apparatus that detects a load of an operation that is being performed by the operator and that outputs operation information indicating the detected load of the operation, a storage device, and a signal processing apparatus. The signal processing apparatus accumulates, while the operator is performing the operation, the information for identifying the operator, the biological information, the operation information, and time information in the storage device while associating the information for identifying the operator, the biological information, the operation information, and the time information with one another, estimates the biological information regarding the operator at a present time on a basis of a correlation between temporal changes in the operation information and temporal changes in the biological information in past accumulated in the storage device, and determines appropriateness of the operator for the operation by comparing the estimated biological information regarding the operator at the present time and the biological information regarding the operator at the present time obtained by the biometric sensing apparatus with each other.
