The invention relates to the field of agricultural production tools, and discloses an agricultural greenhouse frame structure. The agricultural greenhouse frame structure and the L-shaped, E-shaped and T-shaped connecting device are characterized in that tops of upper upright columns of two outer upright columns of a left canopy frame and a right canopy frame are respectively connected with an upper longitudinal beam by two L-shaped connecting devices to form L-shaped right angles; the upper upright columns and lower upright columns of the two outer upright columns of the left canopy frame and the right canopy frame are respectively connected with a lower longitudinal beam by two E-shaped connecting devices to form three-directional side rods; tops of upper upright columns of middle upright columns of the left canopy frame and the right canopy frame are respectively connected with the upper longitudinal beam by a plurality of T-shaped connecting devices to form T-shaped directional top rods; and the upper upright columns and lower upper upright columns of the middle upright columns of the left canopy frame and the right canopy frame are respectively connected with the lower longitudinal beam by a plurality of crossed connecting devices to form four-directional grids. The agricultural greenhouse frame structure has the advantages that crossbeams, the longitudinal beams, the upright columns and the connecting devices of various joints are manufactured into standard parts, accordingly, an agricultural greenhouse frame can be manufactured conveniently, time and labor are saved, and detachment and material recycling and storage are facilitated.