Introduction Work ability is a multifactorial concept that represents the interaction between human resources and working conditions. It is a dynamic process widely changing during human work life.

Objectives To measure the work ability index among nurses and to assess its determinants and propose strategies to maintain good work ability among this category of workers.

Methods This is a cross-sectional study conducted among a teaching hospital nurses between October 2017 and December 2018. A stratified random sampling method was employed, according to work department and gender to ensure a representative sample of the nurses working in the hospital. Nurses’ work ability was assessed using the work ability index questionnaire including subjective and objective assessments. The job content questionnaire was used to assess job stress and social functioning at work for each participant. Each participant, including physical exercise performed out of work, and homework, underwent a battery of physical functional tests.

Results The mean work ability index score was 41.5± 5.6. Multiple linear regression analysis revealed a positive significant association between mean work ability index score and regular nightshift working schedule, higher decision latitude, stronger grip and a better score of sit-to-stand test. In contrast, male gender, higher body mass index and higher level of perceived stress were inversely associated to the mean work ability index score.

Conclusion Efficient preventive actions based on a higher autonomy in nurses, promoting healthy lifestyles and introducing changes regarding schedule distribution according to the work ability index score would be helpful to promote work ability among nurses. The grip strength test and sit-to-stand test measures, seems to be suitable for nurses’ work ability evaluation by occupational physician.