A portable information device includes: a chassis having an upper cover defining a top face, a lower cover defining a bottom face, and a vertical wall standing between edges of the upper cover and the lower cover to define a side face; a microphone hole that penetrates the vertical wall and opens to the side face; a microphone module in the chassis, including a microphone facing the microphone hole, the microphone module being configured to acquire sound information outside the chassis with the microphone; and a microphone pressure component between the vertical wall and one of the upper cover and the lower cover to be compressed therebetween and press the microphone module against an inner face of the vertical wall.