The main objective of this thesis was to empirically study the primary factors that influence on the performance of new product by domestic small and medium enterprises. Five primary factors were identified from the past studies. They are project leadership, project process, project strategy, innovation culture and government support. In addition, transaction-specific assets and the asymmetry of information and the speed of new product development were included as the moderating variables between the performance of new products and primary factors. The performance were measured success against competitors and the degree to which a sales objective had been achieved. The study was conducted on 207 enterprises which operate in the category of manufacturing businesses. The major finding of empirical study can be summarized in two points. First, when the success against competitors was the performance variable, the factors of ‘project leadership’ and ‘project process’ were significant while the achievement of sales objective was performance variables, the factors of ‘innovation culture’ became significant. Secondly, ‘asymmetry of information’ and ‘the development speed of new product’ were moderating variables. The contributions of this thesis are that the primary factors determining the success of new products by domestic small and medium manufacturers were empirically analyzed while the asymmetry of information and the development speed of new product were found to moderate the performance of new product.