Antenna structures with low side lobe levels are normally the main goal during antenna design. In this paper, a new method for reduction of radiation pattern side lobe level in phased array antenna with uniform and non-uniform weighting is presented. In this method, by changing the array elements weight or adding several elements, such as SLC technique, the pattern with low side lobe level can be achieved. According to the design, in an array with uniform weighting, the value of SLL in third side lobe to next more than -10 dB can be reduced so that main beam width changes less than 3% and variations of gain is negligible. Since in applications non - uniform weighting is used, here a new method for side lobe level reduction in phased array antennas radiation pattern by Taylor weighting is presented. In this method, by use of uniform weighting results, the weight vector of array modify so that side lobe reduction in resultant pattern is perceptible. In this method, the value of SLL in third side lobe to next, ratio to primary Taylor weighting can be reduced so that main beam width approximately 1-2% changes and variation of array gain is negligible. Since in phased array antennas, location of main lobe can be set electronically by applying proper phase in arbitrary angle, performance of this method in pattern scanning is considered and shown in both ways that this method is independent of the main lobe location.