A portable radiation imaging apparatus improves visibility while moving by arranging the supporting column in the low-position. A base 46 is at a bottom end of a supporting column 41 and is fixed to turntable 78. A surface holding bearing 60 has an inner ring 61 and an outer ring 62 between the turntable 78 and a bottom plate 79. The inner ring 61 of the surface holding bearing 60 is fixed to the turntable 78 and the outer ring 62 is fixed to the bottom plate 79. The turntable 78 revolves with the supporting column 41 around the revolving center C, as the center, of the supporting column 41 and the turntable 78. An idler element 65 has a first circumference 63 and a second circumference 64 is installed to a circumference of the surface holding bearing 60. The revolving-side stopper 81 and the fixing-side stopper 82 regulate the idler element 65.