Increasing agricultural productivity is strongly associated with good quality agricultural inputs, price and quality of management. The availability of input in this case rice seeds, farmers still face difficult obstacles determines the sale value of the product, because the practice of monopoly and oligopoly often occur in agriculture. The purpose of this study was to analyze the structure of the rice seed market in East Java. This research was conducted in three districts in East Java, namely: Malang, Mojokerto, and Sumenep. Methods in reviewing the structure of the market by looking at indicators of the level of market concentration, product differentiation, market entry barriers and level of knowledge is by using analytical tools market (market share), CR4 (Concentration Ratio for Biggest Four), Index Hirschman Herfindahl, and Index Rosenbluth. Based on the results showed that the Rosenbluth index analysis tools are relatively suitable for measuring the structure of the rice seed market in East Java, which is a competitive market. This is evidenced by the market concentration does not occur in the three districts. Product differentiation is not the case, in which the varieties can be in the production of various forms of business units. There are no barriers to entry and exit in the market as evidenced by the increasing number of producers in 2014-2015. Almost every manufacturer has knowledge of the location and the price of seed sources of origin, as well as knowledge of the retail price of rice seed products and location-specific marketing.