Purpose: Many studies have investigated the impact of the No Child Left Behind (NCLB) Act and its sanctions on students and teachers. Little research, however, has systematically examined the relationship between NCLB and its sanctions and school principals. Given the importance of school leadership and the accountability systems implemented at different levels of government, there has been a need for research that examines how school leaders behave under the accountability pressure. Research Method: Using the Schools and Staffing Survey data, the Principal Follow-up Survey data, and detailed school-level adequate yearly progress (AYP) and assessment data systematically collected from 45 states, I investigate the association between NCLB sanctions and principals' working conditions, job stress level, and turnover behaviors. I use a distance variable as a key matching variable in propensity score matching and estimate the association. Findings: I find strong evidence that NCLB sanctions are associated with a higher level of principals' job stress and a higher turnover rate. These findings hold even after controlling for the influence of state accountability systems. I do not find evidence that these associations are moderated by principal or school characteristics. I also find little evidence that job stress is a mediator of the relationship between NCLB sanctions and principal turnover. Implications: Sanction-based accountability pressure appears to make the principalship more stressful and lead to turnover. Policy makers currently redesigning state and local accountability systems under the Every Student Succeeds Act may include support programs for school leaders to reduce their job stress level and retain them for a longer period of time.