The objective of this study was to evaluate the association of individual characteristics, health problems, lifestyle factors, and work-related factors with work ability among Dutch construction workers. In this cross-sectional survey, the study population consisted of 19 507 Dutch construction workers who had participated in a voluntary periodic medical examination in 2005 and for whom complete information on laboratory tests and spirometry was available. The main outcome of the study was work ability, measured by the work ability index. Independent variables consisted of physical and psychosocial work-related factors, individual characteristics, lifestyle factors, and some objective health indicators. Multiple linear and logistic regression models were used to determine the influence of different factors on work ability. Physical workload and, to a less extent, psychosocial factors at work together explained 22% of the variability in work ability. Age, leisure-time physical activity, lung obstruction, and cardiovascular risk profile explained about 10% of the workers' ability to work, but, when adjusted for work-related risk factors, their effects became very small. Awkward back posture, static work postures, repetitive movements, and lack of support at work had the highest influence on work ability. In the construction industry, work-related risk factors were the most important in association with work ability. This finding suggests that interventions aimed at preventing construction workers from dropping out of the workforce should primarily focus on reducing physical and psychosocial load at work.