After years of development of laser cladding forming technology, it has made many successful industrial applications. However, how to control the process to achieve the best forming results? We need study the relationship between the processing parameters and the forming accuracy to find the ultimate best solution. We prepare the 316L stainless steel specimens using the laser cladding forming to investigate the influences of processing parameters on geometric characterizations. Five parameters are defined to describe the geometric characterization of single layer cross section, and then the measurement data is processed with the linear regression method to establish relations between processing parameters and defined parameters. In addition, the laser cladding parts prone to two types of typical defects: micro-cracks between grain boundaries and poor fusion defects between two layers.