The literatures show that in all marketing strategies, two important strategies highlight food stores are advertising and R & D. Due to advertising with continuous and accumulative effects and R & D improving product quality which can raise food stores' sale to get the maximal profit. This study investigates the advertising and R & D strategies of packet polished rice and specify a dynamic, partial equilibrium analysis model which includes food store advertisment, and R & D strategies. The theories framework consists an optimal control theory, according to the feature of rice industry, advertising activity, and the effect of R & D, to set the objective function, state equation, inital condition, and transversality condition. The regression analysis is applied to find the concerned parameters. By using Pontryagin's maxium principle, the optimal turnpike of food store's advertising, and R & D strategies can be solved. The main results are summaried as following: 1. Advertising budget / sales revenue=32%. 2. There is an positive relationship between advertising budget / sales revenue and elasticity of goodwill. 3. There is an inverse relationship between advertising budget / sales revenue and depreciatory rate of goodwill. Finally, according to the feature of equilibrium solution, the paper suggests the government's policy reference and assist food stores to make optimal advertising and R & D strategies.