Shelf-life of dehydrated foods can be predicted by several factors including water activity (a_w), moisture content, types of lipids present in the products and environmental conditions. Studies have shown that reduced overall acceptability and spoilage of foods are highly related to a_w and stability of lipid moiety in food products. Storage stability of dehydrated bovine milk with respect to a_w and lipid oxidation have been reported extensively, while few studies have been conducted on powdered goat milk (PGM) products. The objectives of this study were to determine changes in a_w, pH, lipid oxidation of the PGM during storage, and evaluate the stability of PGM products in relation to a_w, moisture content, peroxide value (POV) stored under different temperature and time treatments. Three batches of commercial whole PGM were purchased at a local retail outlet at Warner Robins, Georgia. Each batch of the experimental PGM samples were placed in 120 mL size light-proof amber glass bottles in triplicates, and stored at 4°C and 22°C for 0, 2 and 4 mo. At each storage period, samples were tested for differences in basic nutrients, moisture content, water activity, pH, peroxide value (POV) and their correlations between these parameters at different storage time and temperature treatments. Results showed that there were no differences in levels of moisture (%) and a_w between the 2 temperature treatment groups. The respective mean a_w for 0, 2, and 4 mo at 4°C and 22°C were 0.266, 0.251, 0.243; 0.291, 0.266, 0.219, suggesting that a_w and moisture contents were significantly (P < 0.05) reduced during the 4 mo storage. No differences were found between temperature × storage interaction effects. Significant (P < 0.05) differences were found in POV among different storage time and temperature treatments. We concluded that the a_w and moisture content of the commercial PGM were decreased by storage period, but not affected by temperature, while lipid oxidation of the PGM was significantly affected as the storage time advanced.