Nowadays, in the era of "Internet +", the popularity and convenience of mobile phones make the process of communication and the spread of communication information more rapid and effective. Convenient mobile communication makes employees be in the state of "on the go, ready to work" all the time, even after work, blurring the boundary of work and family. Using mobile phones to work during non-working hours becomes a common state, which has brought about a series of positive or negative effects on employees. Previous studies have found that using mobile phones to work after working has a negative impact on employees' positive emotions, and a positive impact on emotional exhaustion and work-family conflicts. In addition, it will also interfere with the employees' recovery process and significantly reduce employees' happiness. Therefore, how to correctly deal with the official usage of mobile phones during non-working hours has become a problem that management scholars and enterprise supervisor must attach great importance to. Based on the theory of Job Demands-Resources model and Effort-Recovery model, this paper uses the diary method to explore the spillover effect of official usage of mobile phones during non-working time on employees’ life satisfaction. Using the job satisfaction scale, mobile phone usage behavior scale, psychological disengagement scale, and motivation for phones use scale, 968 valid data were obtained through an online diary study of 88 employees for 5 consecutive days. First, common method biases were examined by Harman single factor method. Then correlation analysis and regression analysis were conducted to acquire the overall relationships between variables in the hypothesized model. The results indicated as follows: (1) Using phones to work during non-working hours had a significant negative impact on employees’ life satisfaction; (2)The relationship between official phones usage during non-working hours and employee life satisfaction was mediated by psychological detachment; (3) The relationship between official usage of mobile phones during non-working hours and employees’ psychological disengagement was moderated by the motivation of mobile phones’ official usage.. It is concluded that the official usage of mobile phones during non-working hours had a negative impact on the normal psychological detachment process of employees after work, and had a negative spillover effect on life satisfaction. The autonomous motivation of using mobile phones to work could effectively alleviate the negative effects of official phones usage to work during non-working on life satisfaction. The psychological detachment level of employees who have high autonomous motivation of the official usage of mobile phones increased with the increasing of working frequency and duration of the official usage of mobile phones during non-working time. The conclusions drawn in this study expand the application scope of Effort-Recovery theory. At the same time, on the individual level, it provides a certain theoretical basis for individuals to effectively manage their cross-domain behaviors and adjust their own state; on the organizational level, practical advice is provided for organizations to improve employees’ job satisfaction and to create an organizational atmosphere which is more conducive to employees' active working.