Nowadays, interference is a key problem in wireless communication networks. To solve this problem, researches and also wireless communication industries try to propose efficient methods to deal with interference. One of the most important methods to mitigate interference is Interference Alignment. Interference Alignmet is a management technique that align interference from other transmitters at each receiver in the least possibly dimension suace and as a result, provide the remaining dimensions for free interference signal. Practically, to obtain predicted degree of freedom by Interference Alignment, precoding and receiver matrix should be designed. An uncoordinated interference is an example of interference which cannot coordinately aligned with interference from coordinated part and consequently, the performance of Interference Alignment approaches are degraded. In this thesis, two rank minimization methods are proposed to enhance the performance of Interference Alignment in the presence of uncoordinated interference sources. Firstly, a new objective function is chosen then, a new convex relaxation is proposed with respect to the uncoordinated interferences. Moreover, schatten-p-norm used as surrogate of rank function and an iterative algorithm is implemented to solve optimization problem. Finally, simulation results show that proposed methods can obtain considerably higher multiplexing gain than other approaches in the Interference Alignment framework and thus the performance of Interference Alignment is improved. Keywords : MIMO, Interference alignment, Interference Management , Relaxation