The consumption of imported dairy products is high especially in developing countries such as Nigeria, where little or no milk is produced locally. Soy milk is known to be a good source of protein and a good alternative to cow’s milk. The objective of this work is to compare proximate and microbial analyses of yogurts produced using cow’s milk and soy milk blended with banana. The yogurt was processed by the inoculation of cow's milk and soymilk with freeze-dried cultures of Lactobacillus bulgaricus and Streptococcus thermophilus. The moisture content, crude protein, crude fat, crude fibre, ash content, and carbohydrate in the yoghurt were: 86.38%, 3.76%, 3.76%, 0.02%, 0.18% and 5.90% respectively for dairy; 82.87%, 3.60%, 4.17%, 0.04%, 0.84% and 8.48% respectively for dairy-banana; 87.02%, 5.96%, 1.44%, 0.02%, 1.53% and 4.03% respectively for soy; and 82.94%, 4.82%, 2.84%, 0.06%, 1.80% and 7.54% respectively for soy-banana. Highest lactic acid bacteria count, total viable count, and yeast and mould count were found in soy-banana to be 8.4 × 10³ CFU/g, 3.3 × 10³ CFU/g and 4.9 × 10³ CFU/g respectively at ambient temperature. At refrigeration condition, total viable count, yeast and mould count and total coliform count were found to be nil. A test of the significance of correlation in proximate analysis and sensory evaluation confirms that there exists a trend between the samples at 95% significance level. Respondents’ preference in yoghurt was in the order; Dairy > Dairy banana > Soy banana > Soy. The inclusion of banana in the production of yogurt is a means of value addition to banana which also reduces wastage by preventing postharvest losses.