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Ultra-high-molecular-weight polyethylene (UHMWPE) fibers reinforced polyethylene (PE) matrix composites are attractive materials for applications such as ballistic protection, satellite radiation shielding, and implants. However, the UHMWPE fibers do not bond well with the PE matrix and a very good interfacial bonding is essential to yield composites with good mechanical properties required for the identified applications. Hence, this study is focused on identifying the best surface treatment to maximize the bonding between a commercially available Dyneema UHMWPE fiber and a high density polyethylene matrix (HDPE). The effect of three fiber surface treatments, plasma treatment, chromic acid treatment, and sol-gel derived organic-inorganic hybrid coatings on interfacial shear strength (IFSS) was studied using a fiber pull out test. The treated fiber surfaces were examined using scanning electron microscopy, Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy to support the analysis using IFSS. The fiber surface became rough after treatment, which increased with treatment time. The FT-IR and XPS spectra revealed an increase in the atomic ratio of O/C (except for chromic acid treatment) and Si/C after different treatments, when compared to untreated fibers. Oxygen containing groups were found prominently on the surfaces of the plasma and chromic acid treated fiber surfaces suggesting an increase in the surface roughness due to surface etching. The IFSS increased with decrease in embedment length. Among the three treatments, chromic acid treatment for 1 minute resulted in the maximum enhancement of the IFSS over untreated fibers. Treatment in oxygen plasma for 6 minutes and in sol-gel solution for 1 minute resulted in an enhancement slightly lower than that due to chromic acid treatment.