The present invention relates to a folding apparatus for frame of walk-substituting cart, which comprises a frame and an adjustable device. The frame is divided into a front frame part and a rear frame part. The adjustable device is installed between the front and rear frame parts. Two fixing stands are fitted on the adjustable device for further secure connection to the front and rear frame parts, respectively. Still, at least two crank linking rods are pivoted between the two fixing stands, and an auxiliary adjustable unit is pivoted between one crank linking rod and a fixing stand. Accordingly, with the auxiliary adjustable unit, the crank linking rods and two fixing stands pivoted to each other can be driven, and then further movably secured to the front and rear frame parts of the two fixing stands for spreading and drawing-in movements. The front and rear frame parts can be folded to further shrink the whole size of the cart to achieve essential efficacy and purposes of convenient transportation, arrangement and storage.
