Electron spin resonance (ESR) was employed to investigate the effects of composition and temperature on the FeIn2xCr2-2xS4 semiconductor system. The samples were synthesized using Chemical Vapor Transport (CVT), and their structural characteristics were analyzed through X-ray diffraction and Scanning Electron Microscopy (SEM). For magnetic characterization, magnetization curves M(H) and temperature-dependent magnetization curves M(T) were obtained under both zero-field and field cooling conditions. A paramagnetic behavior was observed for all samples above 180 K, transitioning to a potential long-range spin-glass-like behavior below this temperature. By comparing the results with those presented in the literature, we suggest a reentrant spin glass behavior for the samples with higher Cr concentration. The Electron spin resonance (ESR) spectra revealed asymmetric signals indicative of strong magnetic anisotropies. The inverse of the normalized area in the ESR spectra revealed three distinct regions above the Néel temperature; this observation is consistent with the sensitivity of the lattice parameters of indite. The study elucidates the intricate magnetic behaviors influenced by composition and temperature in the FeIn2xCr2-2xS4 semiconductor system, contributing to a deeper understanding of the material’s properties. This comprehensive investigation, utilizing a range of analytical techniques, advances our knowledge of the system’s magnetic characteristics and provides valuable insights for future research in related semiconductor materials.