In today’s competitive environment many companies are shifting their production strategy from Make-to-Stock to Make-to-order (MTO) system. The reasons are to cater product as per the need of customer and to reduce inventory holding cost. In MTO system, production starts only when order arrives to the shop floor and gets confirmed. Production planning of such system includes scheduling of orders to the production periods and allocation of workers at different work centers.  Complexity in such environment arises when the time to produce products is skilled dependent and from the shop floor condition. Under such situation, efficient scheduling of orders and allocation of workers at different work center play a major role to improve system performance. This research developed a mathematical model for workers allocation problem in a job shop production environment with an objective of minimizing makespan.