Thalassiosira weissflogii microalgae are valued not only as sources of biofuels and bio derivatives, but also as important and nutritious food sources in the aquaculture industry, particularly in shrimp seed production. To develop the efficient biomass production processes, it is necessary to optimize the nutritional parameters of the growth medium specific to each species. In this study, response surface methodology (RSM) was used to optimize nitrogen (N), phosphorus (P), and silicon (Si) concentrations for maximizing the growth rate of T. weissflogii microalgae. The results indicate that N was the main nutrient parameter affecting microalgae growth, with a regression coefficient of 0.03 (p-value < 0.05). An optimal set of conditions, including N concentration of 11.815 mg/L, P concentration of 0.841 mg/L, and Si concentration of 9.173 mg/L, was recommended by the model, predicting a maximum growth rate of 0.276 day-1.