Background: Back pain represents one of the most common diseases across various populations of workers worldwide. This study analyzes the prevalence and severity of back pain, based on selected demographic variables, and the relationship with physical activity among school teachers. Material and Methods: The study included 998 professionally active teachers (840 females and 158 males) from the southern part of Poland. Validated psychometric tools, namely: 1) for evaluation of disability due to back pain – a Polish version of the Oswestry Disability Index (ODI) and Neck Disability Index (NDI), 2) for physical activity assessment – the Subjective Experience of Work Load (SEWL) as well as the authors’ supplementary questionnaire, addressing demographic and anthropometric variables were used. Results: There was no correlation between age and the NDI scores in females (r = 0.027), in contrast to males (r = 0.202; p ≤ 0.05). Statistically significant correlations (p ≤ 0.05) were reported between: age and the ODI, in both females (r = 0.219) and males (r = 0.180). No associations between the body mass index (BMI)-ODI, and BMI-NDI were found. In the case of women, disability related to low back pain (LBP) had a negative impact on the indicators of their activity during work, sports, and leisure time. In the case of men, the NDI and ODI scores did not differ, based on activity indicators. Conclusions: Our findings confirm that back pain represents a serious concern among teachers. Age appears to be a prognostic factor, while no association between the BMI and LBP has been revealed. The limitation of physical activity leads to more frequent back pain. Med Pr 2015;66(6):771–778