Background: The aim of this study was to determine the influence of moderate depression determined based on Research Diagnostic Criteria for Temporomandibular Disorders (RDC/TMDs) Axis II on the bioelectrical resting activity of temporal muscles and masseter muscles. Methods: The research participants were 68 healthy adult women. Of these, 46 people h (mean age: 22 ± 1 year) who had no temporomandibular disorders were selected for the research. They were divided based on results from RDC/TMDs (Axis II: scale’s measurement) into the study group with a moderate level of depression (23 people), rest of participants without symptoms of depression were classified to control group (23 people). The resting activity of temporal muscles and masseter muscles was examined by using BioEMGIII electromyograph. Two statistical analyses were used: Shapiro–Wilk test and Mann–Whitney U test. Results: Despite higher mean tensions of temporal muscles and masseter muscles in the group with depression, results findings were not statistically significant (p > 0.05). Conclusions: Moderate depression determined based on the RDC/TMDs II axis questionnaire is not related to the resting activity of selected masticatory muscles. Further research should be continued on a larger group of respondents in order to establish the relationship between psychological factors and bioelectrical parameters of the masticatory muscles.