The invention relates to a preparation process of hydrogen-rich water. The preparation process comprises the following steps of modifying tourmaline powder, mixing the modified tourmaline powder with brucite powder, active carbon and polyethylene powder, which are directly bought from the market to prepare a hydrogen-rich water mixture, heating the hydrogen-rich water mixture to prepare a hydrogen-rich water ball, placing the hydrogen-rich water ball into a closed reaction tank, introducing the degassed pure water into the reaction tank, stirring the degassed pure water and the hydrogen-rich water ball to prepare the hydrogen-rich water, and filtering and filling the hydrogen-rich water. The hydrogen molecule content in the processed water is 20 times that in ordinary weak alkaline ion water, the capacity for eliminating the acid substances in the human body can be improved by 20 times, the high hydrogen content, weak alkalinity, negative potential and small-molecular water are integrated, the acidity and alkalinity of the human body can be balanced, and different diseases can be effectively prevented.