According to researches, one of the productivity barriers among many organizations is assembly line balancing problem, which needs scientific models to be solved. Given the importance of line balancing, complexity of line balancing in the U-line arrangement, diverse demanding of customers and on the other hand, very few studies conducted to consider several objectives simultaneously in the field of balancing the assembly line,   this paper aimed to develop a new approach for U-line assembly line balancing for mixed products, independent of the production manufacturing sequence in which machineries and workers are simultaneously considered as two potential capacity limitations titled as dual constraint of resources and in terms of a two-objective mathematical model, the mixed integer was presented aimed at minimizing the number of stations needed in a line and minimizing the total cost of operators. Validation and better description of the model is shown by two numerical examples. The results show the effectiveness of the mentioned technique and improvements in goals.