The investigated two-mica granite at Harhagit is mostly enriched in U-, Th, Zr-bearing minerals. Uranothorite, thorite, zircon, xenotime and monazite are presented in the investigated granite, and have been confirmed by using an energy dispersive spectrometer (EDS) unit. The measured radionuclide concentration, including uranium-238 (238U: 69 ± 24 Bq kg−1), thorium-232 (232Th: 64 ± 15 Bq kg−1), and potassium-40 (40K: 1551 ± 217 Bq kg−1), have been determined, all exceed global averages. Statistical evaluations indicate that the distribution of 238U and 232Th is nearly normal, while that of 40K exhibits minor deviations. Assessments of radiological hazards, such as radium equivalent activity (Raeq) and annual effective dose (AED), suggest moderate risks: Raeq values remain under the 370 Bq kg−1 safety limit, but AED levels surpass worldwide norms. The calculated Excess Lifetime Cancer Risk (ELCR) indicates a minor yet substantial health concern. Multivariate statistical approaches, including Pearson correlation, principal component analysis (PCA), and hierarchical clustering, have been employed to elucidate the intricate relationships between radionuclides and hazard parameters. Uranium-238 has been identified as the predominant factor in radiological risks, while 232Th and 40K have been observed form distinct clusters, reflecting their contrasting geochemical dynamics and roles in natural radioactivity. These insights emphasize the necessity to evaluate the geological and radiological attributes of granite, particularly for ensuring its safe application in construction and industrial contexts.