In this research, a new model for cost-oriented assembly line balancing problem has been presented that consists of labour and equipment cost. The approach of this model for these costs is coincided with real condition of assembly lines and yield possibility of using common equipment amoung tasks. The objective function and constrains of this model has been shown by mathematical relations and also some relations for lower and upper bounds of objective function have been presented. Genetic algorithm has been used for solving the problems of this model and the best parameters of this algorithm for different size of problems have been found. Also the performance of suggested genetic algorithm has been compared by a famous method named RTA (Random Task Assignment) and lower bound of objective function. The results of these experiments indicate better performance of the genetic algorithm in quality of solution and computing time.