This research tested the influence of work connectivity behavior afterhours (WCBA) on work-family balance.Work-related rumination, including affective rumination and problem-solving pondering, was considered the mediation to study the mechanism of such influence.Furthermore, boundary segmentation preference was introduced as a moderator to explore the double-edged sword effects of WCBA on work-family balance.We collected 393 valid questionnaires in two periods and reached the following conclusions: (1) WCBA negatively predicts work-family balance; (2) WCBA positively predicts affective rumination which negatively predicts work-family balance and positively predicts problem-solving pondering which positively predicts work-family pondering; (3) both the effect of WCBA on work-family balance and the indirect effect of WCBA through workrelated rumination on work-family balance are moderated by boundary segmentation preferences, which are both attenuated when boundary segmentation preference is higher.We discussed the conclusion of this research and drew theoretical and practical inspirations.