Climate change has an impact on plant growth, including mint. Mint grows optimally in environments with low temperatures and high humidity. Erratic climate change has the potential to reduce mint growth. Biochar is a soil enhancer that can improve soil fertility and soil water availability. Liquid Organic Fertilizer (LOF) is able to provide the nutrients needed by plants so that it has the potential to increase mint growth. This research was conducted in August 2022 - June 2023 in the greenhouse of the Agriculture's Faculty, Sebelas Maret University, Surakarta. The study used a factorial Randomized Complete Group Design (RCBD), which consisted of two factors, namely biochar and fish waste LOF. The types of biochar consisted of no biochar treatment, palm fiber biochar, and rice husk biochar. Fish waste LOF consisted of no LOF treatment, 5 ml/L water, 10 ml/L water, and P3 = 15 ml/L water. The results showed that the application of palm fiber biochar and 5 ml/L fish waste liquid fertilizer can increase plant fresh weight and plant dry weight. Giving palm fiber biochar can increase plant fresh weight, while the addition of rice husk biochar can increase leaf area and plant dry weight. This research has implications to knowing the interaction of biochar type and LOF concentration, getting the appropriate biochar type to increase mint growth, and getting the appropriate LOF concentration to increase mint growth. concentration that is suitable for increasing mint growth.