A foldable frame includes spaced-apart first and second support rods, a first bar having a first end connected pivotally to the first support rod, a second bar having first and second ends connected pivotally and respectively to the second support rod and a second end of the first bar, a sleeve disposed slidably around the first bar and movable to a juncture of the first and second bars when the bars are unfolded so as to limit relative movement between the first and second bars, and a control unit having a cable connected to the sleeve for pulling the sleeve away from the juncture of the first and second bars so that the first and second bars can be folded.