Abstract: Happiness is a comprehensive evaluation of people’s life, which can be used as an important reference to improve people’s well-being. Due to the different allocation of time to participate in different activities, the satisfaction and happiness obtained are also different, thus this study investigates the change of residents’ happiness through the change of time use pattern. Based on the China national time use survey data collected in 2008 and 2018, the three-stage least square method is used to evaluate the improvement of people’s livelihood in China by analyzing the impact of personal attributes and external environment attributes on time use patterns, as well as the impact of time use patterns on happiness. The study found that the happiness of Chinese residents increased significantly during the past decade. In terms of personal attributes, people with higher income and education levels are happier. In terms of external attributes, the increase of per capita number of schools, per capita area of park green space and per capita number of hospitals in the living city can improve residents’ happiness, while the increase of consumer price index will reduce residents’ happiness. From the perspective of activity, more time devoted to paid work, unpaid family services, sleep and personal care activities, meals or other food, use of mass media activities, leisure and entertainment activities, and fitness activities can improve residents’ happiness. In order to further improve the happiness of Chinese residents, it is suggested to improve the quality of employment and people’s income, enhance the efficiency of transportation, increase the investment of educational resources, expand the supply of medical services, and promote the construction of ecological civilization.