This research aimed to develop goat milk yogurt powder by spray drying. Firstly the activities of two prebiotic types (inulin, DP = 2-60) and (oligofructose, DP = 2-10) at different concentration (1-4%w/v) and properties of goat milk yoghurt were measured. The result showed that inulin was more specific to the growth of bacteria than oligofructose. Increasing the prebiotics would increase viscosity of goat milk yoghurt. In the second step, the optimum conditions of making goat milk yoghurt were investigated by varying amount of inulin (1-5%w/w) and sugar (4-10%w/w). The viscosity was measured and the sensory qualities were evaluated. The response surface methodology (RSM) was used to determine the optimum condition. It was found that the optimum amounts of inulin and sugar were found to be 3%w/w and 9%w/w. In the third step, the optimum conditions of spray drying were investigated by varying amount of maltodextrin (5-15%w/w) and inlet drying temperature (160-180°C) at constant feed rate of 40 ml/min. The water activity (aw), moisture content, solubility and particle density of powder were measured. It was found that the appropriated condition of spray drying was 15% maltodextrin and inlet drying temperature of 170°C. Next step, the optimum condition for rehydrating the yogurt powder at 30°C was studied by varying the ratio of yogurt powder to water (1:2 – 1:4). The sensory qualities were evaluated. It was found that the ratio of yogurt powder to water at 1:2 had the highest overall acceptability score. Finally, the yogurt powder was packed in laminated pouch (PE/Al/PE) under nitrogen gas flushing and kept at 30-55oC to investigate the qualities changes during storage for 10 weeks. The result showed that increasing storage temperature and time decreased solubility, total bacterial count and Streptococcus thermophilus but increased color change, thiobarbituric acid, moisture content and aw. The taurine content of the sample stored for 10 weeks was lower than the initial taurine content and increasing storage temperature decreased taurine content. The overall acceptability score of goat milk yogurt powder storage at 55, 45 and 300C were lower than 3 (5 - hedonic scale, 3 = neither like nor dislike) at