The invention provides a plate flexible pattern paint spraying mechanism of a paint spraying assembly line and a pattern mold assembly of the paint spraying assembly line, and discloses the pattern paint spraying mechanism which is applied to the paint spraying assembly line and can perform local paint spraying on plates quickly and the pattern mold assembly of the paint spraying assembly line. The mechanism comprises a pushing assembly and a positioning assembly; the front end surface of the pushing assembly is a pushing surface; the back end of the pushing assembly is connected with a firstpush-and-pull device; the first push-and-pull device is fixed on a workbench and is used for pushing the pushing assembly to reciprocate in the direction perpendicular to a conveying belt of the assembly line; the front end surface of the positioning assembly is a positioning surface; the back end of the positioning assembly is connected with a second push-and-pull device; the second push-and-pulldevice is fixed on a workbench and is used for pushing the positioning assembly to reciprocate in the direction perpendicular to the conveying belt of the assembly line; and the pushing assembly andthe positioning assembly cooperate with each other to position the stacked plates. The pattern mold assembly comprises paint spraying chambers arranged sequentially; the bottom walls of the paint spraying chambers are arranged in the shape of stairs; and hollowed-out to-be-sprayed patterns are arranged on the bottom walls of the paint spraying chambers respectively.