Restriction of manufacturing resources, as the challenges facing manufacturers, allows them to survive in the current competitive environment, available resources devoted to the best possible to maximize additional value. In literature review related to Operation Sequencing Theory problem, problem as to simultaneous decision making about orders acceptance or reject and scheduling them, it’s referred to as an order acceptance and scheduling problem. In this thesis, acceptance and orders scheduling problem has considered with existing a set of customers which have number of order and it’s assumed that acceptance a customer means accepting all its orders and reject one means rejecting all its orders while each customer order has a specific due date. Also, benefit of acceptance and performing order of each customer considered as total revenues of orders minus their lateness. The aim of this problem to find a set of customers accepted that leads to maximize profit. First efficient solutions in order to decrease computation amount of objective function, using problem properties. Then an algorithm has been proposed by presenting two theorems, to decide accepts or rejects some of customers and decrease problem dimensions. This algorithm, in many cases, decreases considerably problem dimensions. A heuristic and mathematic model in order to obtain desirable solution in the short time and an upper bound which exhibits better performance by rising problem dimensions, other achievements of this thesis is considered. In all these cases, the branch and bound method with the three dominant rules are used for decreasing search space. Number of 1350 problems up to 50 customers randomly generated and computational results show that 95 percent of these problems have solved in reasonable time and found optimal solution