This study examined the relationship between linear programming and product mix of paint manufacturing firms in Port Harcourt. This study adopted a correlational survey research design. The population of the study was 10 selected paint manufacturing firms in Port Harcourt as retrieved from Nigerian business directory (2024). 3 managers were selected from each firm multiplied by 10 firms gives us a total of 30 respondents. Structured questionnaire was used in data collection. The result of the Cronbach's Alpha reliability test indicates .804 which is above .70 which implies that the items are reliable. Pearson product moment correlation was used to test the hypotheses using SPSS (statistical package social sciences). The study revealed that there is a significant relationship between Ellipsoid Linear Programming and Product Mix of paint manufacturing firms in Port Harcourt. There is a significant relationship between Graphical method Linear Programming and Product Mix of paint manufacturing firms in Port Harcourt. There is a significant relationship between Simplex Linear Programming and Product Mix of paint manufacturing firms in Port Harcourt. In conclusion, Linear programming is a powerful mathematical tool that can be effectively utilized by paint manufacturing firms in Port Harcourt to optimize their product mix and maximize profits. The paint manufacturing firms should conduct a thorough analysis of market demand for different types of paint products to identify profitable opportunities for product mix optimization.