To provide a mobile information terminal with enhanced user- friendliness.

An operation part 9 of a foldable mobile phone 1 of this invention partly wider than a lower case 3 is pivotally supported to a front face 3A of the lower case 3, a couple of faced side faces and a rear face of which can be gripped by a user in one hand, around a turning shaft 30 nearly perpendicular to the surface 9A of the operation part 9 in a freely turnable manner. Turning the operation part 9 to position itself to be projected outward more than the width of the lower case 3 can apparently extend the width of the lower case 3. The user can operate various operation keys by both the thumbs while more stably holding the lower case 3 in both hands in the cross direction thereof. Thus, the user-friendliness can be enhanced.