Background: The aim of the work is to determine the effectiveness of deep tissue massage therapy on mobility and pain of the thoracic spine. Material and methods: The study involved 18 women and men aged 46–63 years doing office work. Functional diagnostics was performed prior to the therapy (study I), after the procedure (study II) and after 30 days (study III). The Otta test for flexion and extension of the spine, pectoralis major muscles length test, chest circumference measurement, and NRS were used. In the statistical analysis mean and standard deviations were determined and the following tests were used: Mann-Whitney U, Spearman's Rank Correlation, Pearson’s Chi2, Shapiro-Wilk, Friedman, and ANOVA. Statistical significance of the differences was estimated at p