Happiness at work could be defined as feelings and pleasure that an individual experienced after attainment of individual purpose and the full realization of his/her potential at work. It is also a dynamic process which requires continued effort and the organizational and individual investment, including broad structures such as work engagement, flow experience, thriving at work, job satisfaction and positive emotions at work. Given its complexity, it is necessary to simultaneously measure happiness at work at transient, person and unit level. With the methodological advances, the research in this area has now displayed a tendency to combine both inter-personal and intra-personal differences. Integrating the organization and work environment, individual characteristics as well as the interaction between person and the environment, the dynamic multilevel model of happiness at work highlighted the dynamic characteristics of happiness at work and postulated that the satisfaction of human basic psychological needs are the mechanism underlying happiness at work. The dynamic Spillover-Cross model suggests that happiness spills over in different life domains and transfers between work teammates or couples, and thereby helps to promote effect research of happiness at work at different levels. More empirical studies are needed to test the dynamic causal models of happiness at work, and to explore the psychological mechanism of how the happiness at work at different levels influences the performance. Specifically, future studies may focus on the specific indexes of happiness at work such as flow experience, thriving at work, happiness, pride, as well as on intervention procedures.