<p>Enhancing teachers’ work engagement requires systematic exploration of its contributors. Job insecurity has been considered a significant factor; however, other mediators and moderators may affect the relationship between job insecurity and work engagement. The present study tested a model of work engagement involving job insecurity as a predictor, affective well-being as a mediator, and emotion regulation difficulties as moderators of the mediational relationship. In this cross-sectional study, a total of 170 teachers (<i>M</i>_<i>age</i> = 32.22, <i>SD</i>_<i>age</i> = 7.83), selected using the purposive sampling technique, were assessed using standardized measures. The data were subjected to mediation and moderated mediation analysis. The analysis revealed that affective well-being mediates the relationship between job insecurity and work engagement, and emotion regulation difficulties moderate the effect of job insecurity on affective well-being. It implies that individuals with the same level of job insecurity but different levels of emotion regulation difficulties showed differences in their well-being and work engagement. Emotion regulation difficulties influence how job insecurity impacts work engagement. Job insecurity may not be a sufficient condition for reduced work engagement. It may be the difficulty in emotion regulation and consequent poor affective well-being due to heightened negative emotions that affect work-engagement. Helping teachers identify their emotion regulation difficulties and equipping them with functional and adaptive ER strategies may improve their work engagement.</p>