The purposes of the present study were to determine whether extrinsic high-effort/low-reward conditions at work are associated with personal characteristics and the organizational environments. A cross-sectional survey was conducted (76.7% response rate, N=1243) by recruiting the staff caring for people with intellectual disabilities of Taiwan in 2006. Conditions at work were measured using Siegrist's Effort-Reward Imbalance (ERI) model, the questionnaire included 23 Likert scaled items and it divided into three scales: effort, reward and overcommitment. Multiple logistic regression modeling was conducted for extrinsic high-effort/low-reward status in relation to staff and working environmental factors. We found that 15.1% staff were in the low-effort/low-reward group, 35.9% was in the low-effort/high-reward group, 17.9% belonged to the high-effort/high-reward group and 31.1% was included in the high-effort/low-reward group. Controlling for many personal demographic and organizational characteristics, the factors of perceived job support (OR=0.91; 95% CI=0854-0.97), job control (OR=0.954, 95% CI=0.934-0.974), job demand (OR=1.155, 95% CI=1.109-1.203) and job stress (felt sometimes stressful compare to no stress at all, OR=2.305, 95% CI=1.161-4.575) of the staff were significantly correlated to the extrinsic high effort/low reward at work in the multiple logistic regression model. The present study highlights that the service providers need to be aware and understand the experiences that their staff encounters in the organizational, interpersonal and personal level regarding unfair working conditions such as high effort/low reward to improve the positive health of the staff.