Today, water quality reduction and water pollution are some of the challenges in different countries around the world. One way to meet these challenges is to harvest and store rainwater using rainwater catchment systems. By collecting rainwater using rainwater catchment systems, water does not flow on the ground. Therefore, using the rainwater catchment system helps to prevent rainwater from mixing and contaminating with various pollutants. Since the value of rainwater and preventing its contamination in Islamic teachings is important, 63 verses of the Holy Quran are about the importance of water, including rainwater. One of the most important verses is in verse 205 of Surah Al-Baqarah. Also, in several hadith sources such as vasael al_shia, the issue of non-pollution of rainwater has been explicitly mentioned. Although the use of rainwater catchment systems has not been explicitly mentioned in the Qur'an and hadiths, in this article, we attempt to find Qur'an and hadith principles in collecting and storing rainwater with these systems.