In this paper, D-shaped photonic crystal fiber (PCF) based structure has been designed where the chemically sustainable and renowned material gold (Au) is used for high sensing between the core and the analyte. This structure is constructed with pure Silica (SiO₂) to obtain maximum performance. The formal simulation is done by the finite element method. By the simulation, here is obtained the maximum wavelength sensitivity of 66666.67 nm/RIU, high amplitude sensitivity (AS) of -1488.82 RIU⁻¹ for the refractive index of n_a = 1.36 to 1.39. This structure also obtained high resolution of 9.66 × 10^-4 RIU for the x polarization. For finding out the efficient result in the field of biological and biomedical analyte detection, the proposed structure is going to be the suitable choice.