As a rapidly growing network UMTS, the 3rd generation mobile communication system, is designed to provide sufficient capacity for the services requiring high bit rates. The WCDMA technology has been chosen for the technique of UMTS in which all connections are able to use the same frequency band and time thanks to orthogonal and pseudorandom codes. As a result of using the same frequency band, interference management is a key in optimizing the network capacity and coverage. Therefore, a practically applicable algorithm is needed. However, the existing algorithms generally present iterative methods which are difficult to be applied for mobile network operators in that iterative methods require more man power and increase costs. In this thesis, we present a two-step method that will decrease interference in UMTS Networks according to received power measurement results and network initial configuration by adapting antenna tilt, azimuth and Common Pilot Channel (CPICH) power since those parameters have direct impact on coverage area in terms of shape and size. First step calculates base stations antenna downtilt and CPICH power while second step adopting azimuths. The performances of proposed algorithms are obtained considering practical scenarios. The results have shown that antenna tilt, pilot power and azimuth can be used successfully in managing interference for UMTS Networks.