The wrist-worn device has sensors that monitor pulse rate, measure calorie burn and track sleep quality, said Microsoft in a post.
The device would be available in United States in limited quantities from Thursday for USD199.
Earlier Apple Inc unveiled a smart watch on September 9 that will combine health and fitness tracking with communications and will go on sale in early 2015.
Microsoft also launched a health app 'Microsoft Health' which includes a cloud service for users to store and combine health and fitness data.
The Microsoft's Health app will collect data from the fitness band and will work on iPhones, Android smartphones, as well as its own Windows Phone.