Background Work ability (WA) describes the physical and intellectual resources on which individuals can rely to respond to work demands. While several studies have investigated the protective role of work-related psychosocial factors on WA, only a few have examined differences across age cohorts. Moreover, few studies have investigated WA in the educational context and most of those did not consider preschool teachers. Aims To examine the role of psychosocial factors (support from colleagues, support from supervisors, work meaning, reward, skill discretion and autonomy) in sustaining WA among preschool teachers in different age cohorts. Methods A cross-sectional study of preschool teachers employed in the municipal educational services of a city in northwest Italy. Study subjects completed a self-reported questionnaire. Results Among the 706 study subjects, in the 35-44 age cohort, support from colleagues was positively associated with WA. In the 45-54 age cohort, WA was found to be associated with reward and skill discretion while in the 55-63 age cohort, work meaning was significantly associated with WA. Conclusions Our findings indicate that potential protective factors for WA may differ between age cohorts. They also suggest that in order to sustain WA effectively, interventions in working populations should be tailored to employees' ages. (author abstract)