The productivity and quality of natural rubber in Indonesia, particularly in Jambi Province, remain suboptimal, resulting in lower market value compared to rubber from Malaysia and Thailand. This study investigates the potential of coal-derived liquid smoke as an alternative coagulant to improve the quality of natural latex. Liquid smoke was produced using a 3-in-1 pyrolysis reactor operated at 250–300°C for 5 hours and subsequently purified into three grades. Various concentrations (10%, 25%, 45%, 50%, and 60%) of liquid smoke were tested for latex coagulation. Characterization revealed that purified liquid smoke had a pH range of 2.06–2.66, total phenolic content of 11.67–13.13 mg GAE/100 g, and acidity of 11.12–13.06%. Field applications with local farmers in Ladang Panjang Village demonstrated that liquid smoke at concentrations above 40% significantly improved latex quality, with faster coagulation times, reduced impurities, and enhanced resistance to microbial growth. These findings suggest that coal-derived liquid smoke is a cost-effective, environmentally friendly alternative to conventional coagulants, contributing to improved rubber quality and market value.