The invention discloses a control technology of partition board cracks. The control technology comprises steps as follows: door frame partition boards on two sides of a doorway are processed into an inverted L shape according to the height of the doorway, and the door frame partition boards are subjected to water and electricity grooving construction after mounted and fixed in place; an after-pouring joint is reserved between the two door frame partition boards, propping of a tool type propping piece is adopted for the after-pouring joint to stabilize the two door frame partition boards; after the door frame partition boards are mounted stably and shock disturbance of each type of work is ended, the tool type propping piece is replaced with a reinforcement piece to prevent the after-pouring concrete from cracking, a panel header is supported by a tool type support frame, multi-layered plates are applied to two sides for mold closing, and light aggregate concrete is poured; when the partition board body is wholly mounted, form stripping is performed and gridding cloth and polymer anti-crack mortar are adopted for anti-crack treatment. According to the control technology of the partition board cracks, the quality problem of the partition board cracks is solved thoroughly, the complaint rate of proprietors is greatly reduced, the repair cost is reduced, and a good quality effect is realized.