Fluctuations in the stock levels of the ornamental angelfish export market have highlighted the necessity for an effective demand prediction system. In response to this need, the present study undertakes the development of a demand prediction model, employing the Least Square Method, for the ornamental angelfish market. The model is evaluated using a dataset comprising 4166 individual records across three ornamental angelfish samples from the year 2021. The model's predictive accuracy is quantitatively assessed through the Mean Absolute Deviation (MAD), Mean Square Error (MSE), and Mean Absolute Percentage Error (MAPE) compared to actual data. The results indicate a high level of accuracy, with an average MSE value of 39, an average MAD value of 5, and an average MAPE value of 5%. This study's findings contribute valuable insights to the ornamental angelfish export industry, demonstrating the efficacy of the Least Square Method in forecasting demand, and propose potential trajectories for further research.