In this study, carbon and graphite fibers (GFs) using confocal Raman microscopy at 405 nm and 532 nm wavelengths are analyzed to explore the influence of incident laser power and sample temperature on the Raman spectra. At room temperature, the G-band and D-band shifts of turbostratic fibers show a slight reduction with increased laser power, indicating potential surface heating under an inert atmosphere. In contrast, the graphitic fibers display consistent G-band and G′-band positions across varying laser power, with a noticeable decrease in D-band intensity at higher wavelengths. The I_D/I_G′ ratio for GFs—calculated at different excitation powers and wavelengths—is constant at 1.91 ± 0.12, suggesting that these fibers have fewer on-site (sp³ hybridization) defects compared to defect-free graphite, which exhibits a higher I_D/I_G′ ratio of ≈3.5. High-temperature Raman spectroscopy demonstrates linear correlations between Raman shifts and temperature for both fiber types. For GFs, the G-band thermal coefficient (χ_G) is −0.0239 ± 2×10⁻³ cm⁻¹ K⁻¹, and the D-band thermal coefficient (χ_D) is −0.0177 ± 1×10⁻³ cm⁻¹ K⁻¹. For turbostratic fibers, the G-band thermal coefficient (χ_G) is −0.0358 ± 0.004 cm⁻¹ K⁻¹, significantly higher than that of the graphitic fibers—likely due to their greater lattice disorder.