The invention discloses a waist beam structure used for spray anchor supporting. The waist beam structure is internally provided with a plurality of constructional steel bars distributed in a right-angle trapezoid mode. A peripheral stirrup surrounds the outsides of the constructional steel bars. An L-shaped steel wire net piece is arranged between the peripheral stirrup and the constructional steel bars in a sandwiched mode, located at the oblique waist and the bottom edge of the peripheral stirrup, and bound on the constructional steel bars through an iron wire. Fine stone concrete is poured in an inner cavity enclosed by the constructional steel bars, the L-shaped steel wire net piece and the peripheral stirrup. A concrete surface layer is sprayed on the periphery of the peripheral stirrup. Transversely-arranged waist beams and a longitudinally-arranged slope protection pile are fixedly installed on the oblique waist of the concrete surface layer. Metal anchor rods are fixed to the waist beams, and the other ends of the metal anchor rods are inserted and anchored in the fine stone concrete. According to the waist beam structure used for spray anchor supporting, construction is convenient; the construction schedule is accelerated; the construction quality can be ensured; the waist beam structure is economical, practical, safe and stable; and the economic benefit is increased.