After entering WTO, Taiwan faces the challenges of globalization. At the same time, migration of manufacturing industries to mainland China seems to be an endless trend. To avoid failure, firms have to make constant changes, expand their sizes, and seek strategies for sustaining profit growth under the severe competitive environment of today¡¦s global markets. To maintain competitive advantages, small and medium enterprise have to leverage their resources and competences for sustainable profitability and growth by careful strategies formulation. The diversification processes to expand a firm¡¦s size and business fields are related to its competence and its efficiency of leveraging resources. This research is about the relationship between resources based view and diversifying strategies. Based on the diversification process of company L, we explore the strategies for the case company by considering changes in industry environment and the company¡¦s conditions ,with the evaluation of the company¡¦s competence and resources. The findings are: 1. The fields of new businesses for diversification of a company are restrained by their existing resources. 2.The diversification will be more likely to success, if the products to be carried in the new business are highly connected to the company¡¦s current customers. 3.The new business will eventually need new resources ,which will be accumulated and become one of the firm¡¦s important resources.