The 1942–43 Challenge Cup was the 42nd staging of rugby league's oldest knockout competition, the Challenge Cup.

[1] All four rounds, including the final, were played as two-legged ties.

The tournament took place over consecutive weeks in March and April 1943.

All the ties were drawn at the beginning of March 1943 to enable the clubs to make travel arrangements in advance.

[2] Aggregate scores shown in brackets Aggregate scores shown in brackets Aggregate scores shown in brackets The final was played over the Easter weekend of 1943 with the first leg played on the Saturday and the second leg the following Monday.