A portable machining apparatus has high operability in tilting a body with respect to a base or in machining a workpiece with the tilting body. A portable machining apparatus placeable on a long gauge placed on an upper surface of a workpiece includes a base placeable on the long gauge, a body including a blade for machining the workpiece, an angular plate fixed to the base to support the body in a tiltable manner and including a protrusion, a body support located between the body and the base and including a guide engageable with the protrusion to allow sliding of the protrusion on the guide, and a spring that urges the protrusion toward the guide.