A unique highly sensitive photonic crystal fiber, to the best of our knowledge, is investigated based on plasmonic material and magnetic fluid (MF) for the simultaneous measurement of temperature and magnetic field sensor. The designed sensor is explored by tracing the different parameters such as birefringence, coupling length, power spectrum, and the peak wavelength of the transmission intensity. The magnetic field and temperature computation are attained simultaneously by examining the linear fitting curve and the movement of transmission peaks. The obtained sensitivity for temperature is 7.1 nm/°C with an exposure range of 25°C to 100°C. In contrast, the magnetic field sensitivity is 12 nm/Oe with a detection range of 160-200 Oe. In addition, the resolutions are -1.245∘ C and 5.53 Oe for temperature and magnetic field, respectively. Our inspected sensor is used to detect extremely low and high values of magnetic fields. The investigated structure is presented with simplification, compactness, easy implementation, and high sensitivity, which is expected to be a good foundation for the advancement of optical sensing devices in the future applications of industries, security, small grids, and environmental systems.