The invention provides a rear suspension structure of a rear transverse passenger car frame of an engine, comprising rear longitudinal beams, a special-shaped connecting bracket and a rear transverse frame with an inner transverse gearbox and an engine assembly, wherein the rear transverse frame is of a prism composed of upper, lower and outer cross beams as well as left upper, left lower, right upper and right lower oblique beams; six parallel vertical beams are sequentially arranged between the upper and lower cross beams; inlaid cavities clamped between the left second and left third vertical beams and between the right third and right second vertical beams are connected with side connecting plates in the special-shaped connecting bracket in an inlaid mode; the side connecting plates are connected with the rear longitudinal beams sequentially through a middle connecting plate and an upper connecting plate; and the side connecting plates are provided with engine suspension bracket mounting holes near the upper cross beam. In addition, left upper and right upper connecting beams, left lower and right lower connecting beams as well as left inner and right inner fixed brackets are additionally arranged so as to further improve the stress stability of the structure. The structure designed by the invention is relatively strong in stress stability, relatively high in safety, relatively high in integration degree and small in space occupation.