Probiotics has been discovered long time ago for its beneficial effect on health when consumed especially to the people who had allergy and gastrointestinal disease. This preliminary study was conducted to find out which vehicles can allow better growth of probiotic. Lactobacillus plantarum was used in this study as choice of probiotic to be cultured in the four types of milk. The pH value was recorded for determination of growths and metabolic activity of the probiotic. Results showed that L. plantarum in soy milk can grow and had a better metabolic activity in the cultured soy milk with pH 3.46 compared to others. The highest growth was recorded at optical density of 1.137 in soy milk at 560nm. This result showed that L. plantarum in soy milk multiply rapidly compared to other milks. As conclusion, soy milk has better development of probiotic as delivery vehicles compare to cow milk, goat milk and coconut milk.