A basket frame of a stroller comprises a connecting device connected between a front frame and a rear frame. The connecting device comprises a first connector having a first pivot part, a second connector having a second pivot part, and a torsion spring. The first pivot part is pivotally connected to the second pivot part. An application of a downward force on the rear frame deforms the torsion spring and causes the rear frame to pivot downward. A removal of the downward force causes a spring return to make the rear frame to return to a fixed position.