Herein, the substitution of Mn in SrTiO₃ is presented as an effective approach to develop functional ferromagnets with spin‐polarized semiconductive band dispersions. The task is performed with the full‐potential linearized augmented planewave (FP‐LAPW) approach based on density functional theory (DFT) as coded in WIEN2k. Exchange and correlation effects are taken into account using generalized gradient approximation (GGA). The strong hybridization between O‐2p and Mn‐3d is accountable for the origin of the semiconductive ferromagnetic ground state in Sr_1−xMn_xTiO₃ (x = 12.5%, 25%, 50%, and 75%). Increase in Mn content in SrTiO₃ crystal causes a significant increase in total magnetic moment values. The optical behavior is investigated by computing refractive index, optical conductivity, dielectric constant, absorption coefficient, and reflectivity within 0–10 eV energy range. Mn‐doped SrTiO₃ shows maximum absorption in the ultraviolet region. The computed physical characteristics suggest a potential usage of Sr_1−xMn_xTiO₃ in optoelectronic and magnetic devices.