The ambivalent experience of superior–subordinate relationships is widespread in organisations and has gradually become an important factor influencing employees to actively engage in extra-role behaviours. However, employees’ constructive deviance is extremely important for organisational development as they are important extra-role behaviours for organisational innovation and change. Owing that academic research on the antecedents of employees’ constructive extra-role behaviours has lacked attention to individual emotional variables such as the leader–member exchange ambivalence, by drawing on self-control resource theory and social cognitive theory, this study examined the effects of leader–member exchange ambivalence on employees’ constructive deviance, as well as the role of ego depletion and role-breadth self-efficacy. Based on a two-point questionnaire survey of 332 employees from different industries in China, the study tested hypotheses with SPSS 27 and AMOS 27 and found that the more leader–member exchange ambivalence, the less likely they were to engage in employees’ constructive deviance, leader–member exchange ambivalence affected employees’ constructive deviance through ego depletion, and when role-breadth self-efficacy is high, the lower the ego depletion of employees with leader–member exchange ambivalence, the more likely they are to engage in employees’ constructive deviance. This study is intended to guide organisations to pay attention to the problem of individual internal conflict arising from superior–subordinate relationships, to remove the barriers to constructive transgression by individuals, and to truly exploit the innovative capacity of individual organisations. The study suggests that managers should pay attention to the negative effects of employees’ perceived ambivalent experiences of supervisor-subordinate relationships, maintain consistency, and build positive social exchange relationships with their employees. Organisations should strengthen the training of leaders and employees to eliminate the serious internal attrition that organisations face from social network relationships. And employees should face the limitations of resources and reduce dependence on the leader–member exchange relationship as the dependence for their work attitudes and behaviours.