THz Plasmonic metasurfaces (TPMs) sensor have emerged as a benchmark principle for harnessing and manipulating light at the nano-scale and enabling to use in optical functionalities for detection of different analytes in liquid and solid phases. Plasmonic sensors with very high sensitivity and precision are particularly important to the fields of chemical and biological materials like ammonia and urea quality monitoring. In this paper, we present a four-band plasmonic metasurface structure with very high sensitivity ( <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">SS</i> ), figure of merit ( <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">FoM</i> ), and magnetic field intensity enhancement (MFIE). Max MFIE in four-band of the proposed plasmonic metasurface sensor have been generated by strong coupling between input waves and surface plasmon polaritons (SPPs) that show very narrow bands, and harness the light in near-infrared regime. The narrow absorption spectra leads the gigantic MFIE in four bands that generated due to the excitation of the SPPs in the edge of the metal thin film and support the Transverse Magnetic (TM) surface mode. The optical responses of the presented plasmonic metasurface sensor have be shown the best characteristics/operation Max sensitivity, <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">FoM</i> and <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">MFIE</i> that obtained as 1300 nm/RIU, 79 and 6.3×10 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">8</sup> , respectively. Results show that the sensor has several high and outstanding performances in comparison with other sensors in the last decade. Also, the presented sensor is valuable and satisfactory in the case of a tunable and compact footprint device. Accordingly, the findings have revealed that the interested four-band plasmonic metasurface is practical work in different sensor applications such as bio-chemical and refractive index sensing.