An increasing number of environmental regulations have shifted the spotlight toward the creation of ecological composite materials. This study examines, the effect of loading fiber and sodium hydroxide (NaOH) surface treatment on the water absorption, mechanical, physical, thermal, and morphological characteristics of coir fibers (CF) reinforced in a Kondagogu gum (KGG) matrix. The mechanical properties enhanced with the 10 wt% of CF composites, achieving tensile, flexural, and impact values of 2.30 MPa, 2.36 MPa, and 715.74 J/m2, respectively. Furthermore, coir fibers were treated with NaOH subsequent increases in the tensile, flexural, and impact properties with 6.08%, 78.38%, and 15.13%, respectively. The scanning electron microscopic (SEM) images, Fourier transform infrared (FTIR) spectrum, and water absorption of the composites were observed to ensure their suitability in packaging applications. With their advantageous hydrophilic properties, reduced density, and ability to remain thermally stable up to 255 °C, the treated NaOH CF/KGG composite is an appropriate fit for the interiors of the automobile sector.