A conceptual framework for product ecosystem was proposed. System dynamic method was used to analyze the effect of system elements in product survival and evolution. First, similarities between the product environment system and natural ecosystem were analyzed. Then, a model for product ecosystem was constructed, and the key relationships between the product and its environment was analyzed by using system dynamic method for describing the effect of environment in product evolution. Lastly, a phylogenetic analysis of self-priming pump was given as an example.