This study aims to explore the growth of P. ostreatus mycelium using mushroom liquid-based culture media. The experiment was conducted using mushroom liquid produced in the laboratory from oyster mushrooms and white button mushrooms. The study evaluated the colonization rate, mycelial density, produced biomass, and incubation conditions. The results showed that mushroom extract liquid has great potential as a culture medium for the cultivation of P. ostreatus mycelium. It promotes faster growth rate and higher biomass content, which maximizes the yield of P. ostreatus mycelium. Moreover, this mushroom extract liquid can be used as a valuable resource for the production of bioactive compounds with antimicrobial and prebiotic properties. It can also be used for further research and application in the food industry.