To provide an information processor for solving the problem of usable time by battery drive, which sometimes becomes a problem in a portable information processor by using a control means, independently of the explicit intention of a user to the information processor.

This information processor is provided with at least one sensor means 32 for detecting the condition of the user to use an information processor 31 or condition around this user as a physical quantity, a condition discriminating means 33 for processing the output signal of this sensor means 32 and discriminating which one of preset conditions corresponds the detected condition, and a power control means 35 for controlling the power consumption of an information processing means 36, on the basis of the result discriminated by this condition discriminating means 33.