Our most valuable natural resource is water, which most of us take for granted. We are more conscious of the significance of water to our existence, as well as its scarcity. Humans need water for a variety of reasons. Water covers the majority of the earth's surface (about 71 percent). Only 1% of the total quantity of water accessible on the earth's surface is fresh and drinkable water, with 97 percent being salty water, 2% being ice and glaciers, and 1% being clean and potable water. In terms of average annual rainfall, India is one of the world's wealthiest countries. It's hard to believe, but Cherapunji, which receives 11000 mm of yearly rainfall, yet has a significant drinking water scarcity. This paper discusses the overview of rain water harvesting, techniques of rain water harvesting, component of rain water harvesting and advantages of rain water harvesting. Though India's average annual rainfall is 1170 mm, it may be as low as 100 mm in the deserts of western India. As a result, rainwater gathering methods are required to meet the water need.