Abstract: A side-inserted cord rolling device for a non-pull cord window blind includes a base, first and second wheels disposed on the base and respectively located near an end plate and an opening provided at two ends of the base, a torsion spring, and two lift transmission cords. The first wheel has top, middle and bottom layers separated by disc portions. The torsion spring connects the bottom layer of the first wheel and the second wheel. An end of the lift transmission cords are connected to the top and middle layers of the first wheel respectively. Another end of the lift transmission cords are inserted through the opening of the base to be located out of the base for being connected with a bottom beam.