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Mast cells (MCs) are recognized for their pathophysiological impact across various inflammatory conditions, notably in allergic responses. There is also limited evidence that suggests a potential link between MCs and diabetes, which prompted us to study the effect of insulin on MC functionality. Initial experiments explored the effect of insulin of MCs on proliferation and maturation, revealing a subtle stimulatory effect on proliferation, but no significant impact on maturation. Insulin had no impact on MC responses to either IgE receptor crosslinking or compound 48/80, an IgE-independent mast cell activator. Further investigations focused on MC lipogenesis and viability, particularly in the presence of lipolytic inhibitors. Results indicated a noticeable proliferative inhibition, in a subset of MCs that were chronically treated with both insulin and lipolytic inhibitors, but no apoptotic effect from the inhibitors was observed. In addition, we observed a very weak effect on MC lipogenesis. Concurrently, gene expression analysis revealed elevated levels of cyclooxygenase-2 (COX-2), a key enzyme in prostaglandin synthesis, suggesting potential implications for inflammatory processes. Altogether, these findings highlight the complex interplay between insulin and mast cell functions, with implications for conditions such as diabetes.