The invention discloses an aligning device for cylinder sleeve casting blanks. The aligning device comprises a base and a swinging arm; one end of the swinging arm is a pivot-rotating end, and the pivot-rotating end is connected with the upper end of the base in a pivot-rotating mode; the other end of the swinging arm is a free end; a material guiding channel is formed in the top of the swinging arm and penetrates through the pivot-rotating end and the free end; telescopic material blocking devices are symmetrically arranged on the two side faces of the swinging arm and are close to the pivot-rotating end; and telescopic parts of the two telescopic material blocking devices are oppositely arranged. The cylinder sleeve casting blanks are aligned before being cut, one cutting machine can cut the multiple cylinder sleeve casting blanks simultaneously, and it is guaranteed that after being cut, each cutting piece is even and consistent. In addition, in the conveying process, the cylinder sleeve casting blanks are subjected to aligning treatment, so that the spaces between the adjacent cylinder sleeve casting blanks on the same conveying path are consistent, continuous work of follow-up machines in the same state is facilitated, and constant adjustment of the working states of the machines is not needed.