The pH of a banana is about 5.5. This means that it is slightly acidic. However, the effect of a banana on your body's pH is very small. A banana's pH level depends on how ripe the fruit is. An unripe banana has a pH level of around 5.6, while a ripe banana has a pH level of around 6.5. The higher the pH level, the more acidic the fruit is. The lower the pH level, the more alkaline the fruit is. Bananas are a good source of dietary potassium and vitamin C. They also contain dietary fiber, which helps to regulate digestion.