Abstract: Hands-free operation is a prerequisite in wearable PCs; a problem in such PCs is that intuitive input or direct input such as pen input or touch panel input is impossible, so that a comfortable input operation cannot be performed. In order to solve this problem, the portable information device of the present invention comprises a portable main body part, and an HMD which is connected to this main body part, and which is mounted on the head. Furthermore, the abovementioned main body part comprises an input display part which displays to the outside image information consisting of a smaller amount of data than the image information displayed on the abovementioned HMD, and which inputs operating information from the outside on a displayed screen, an output part which outputs information to the abovementioned HMD, and a control part which controls the image information that is displayed on the abovementioned HMD on the basis of the operating information that is input in the abovementioned input display part.