UN Sustainable Development Goal 3 states that “Ensuring healthy lives and promoting well-being at all ages is essential to sustainable development.” The sustainable well-being of college teachers deserves attention. Currently, college teachers in China are facing enormous challenges and pressures, which may increase their emotional exhaustion (EE) and hinder the sustainable development of their well-being (WB). Therefore, this study examined Chinese college teachers’ well-being in relation to their work-life balance (WLB) and EE. An online survey was conducted. The valid subjects included 586 college teachers (367 females, 62.6%). We assessed their WLB, EE, and WB. The results revealed that among the Chinese college teachers, (1) WLB was negatively correlated with EE, but positively correlated with WB; EE was negatively correlated with WB; (2) EE partially mediated the relationship between WLB and WB; and (3) College teachers who are male, class tutors, and in public colleges scored higher on EE and lower on WLB and WB than those who are female, non-class tutors, and in private colleges, respectively. The findings indicated that WLB is an important factor for the sustainable development of the well-being of college teachers, and special attention should be paid to college teachers who are male, class tutors, and in public colleges in China.