This study suggested a novel hexa-sectored square photonic crystal fiber (HS-SPCF) for blood serum and blood plasma sensing. The proposed HS-SPCF depicts an eminent sensitivity of blood plasma 66.7% and blood serum73.4% with ultralow low confinement loss 1.55 × 10^–12 and 10.55 × 10^–12 at the wavelength of 1.33 µm for blood plasma and serum. The operating wavelength to measure the optical properties using FEM was 0.6–1.6 µm. The proposed HS-SPCF showed ameliorating performance in confinement loss and relative sensitivity than the previous structures for blood components sensing. In addition, other optical characteristics like high birefringence of 2.6 × 10^–3 and 2.6 × 10^–3, lower EML of 0.21247 (cm⁻¹) and 0.2170 (cm⁻¹), effective area of 6.1 µm² and 6.4 µm², nonlinearity of 21.1(W⁻¹ km⁻¹) and 19.6 (W⁻¹ km⁻¹), numerical aperture (NA) of 0.286 and 0.281 has been achieved for proposed PCF at the wavelength of 1.33 µm. The proposed PCF will be used for biosensing or blood-sensing purposes and a broad diversity of chemical sensing functions.