A portable electronic apparatus having a first case, a second case, and a two-axis hinge mechanism. Positional misalignment between both cases can be easily prevented without relying only on dimensional precision of the components of the two-axis hinge mechanism. The portable electronic apparatus has a hinge (4) for interconnecting the first and second cases so that they can be opened and closed about a first rotation axis (X) and at the same time interconnecting the first and second cases so that they can pivot about a second rotation axis (Y). The hinge (4) has a first case fixing component (122) fixed to the first case, a first connection component (452) connected to the first case fixing component (122) so as to be rotatable about the second rotation axis (Y), and a second connection component (461) connected to the second case so as to be rotatable about the first rotation axis (X). The first connection component (452) and the second connection component (461) are connected to each other with a screw. The degree of tightening of the screw for connecting the first connection component (452) and the second connection component (461) together can be changed when the first and second cases are closed by folding them about the first rotation axis (X).