The effects of polypropylene-graft-maleic anhydride (PP-g-MA) compatibilizers on the morphology and mechanical properties of polyoxymethylene (POM)/acrylonitrile-butadiene-styrene (ABS) blends were investigated. Two types of compatibilizers, PP-g-MA with maleic anhydride 0.50 wt% (PP-g-MA1) and PP-g-MA with maleic anhydride 1.31 wt% (PP-g-MA2) were used to study the interfacial adhesion of POM and ABS. POM/ABS blends with and without PP-g-MA compatibilizer were prepared by an internal mixer and molded by compression molding. Scanning electron microscope (SEM) was used to investigate the morphology of ABS phase in POM matrix. The results found that POM/ABS blends clearly demonstrated a two phase separation of dispersed ABS phase and the POM matrix phase, and ABS phase dispersed as spherical domains in POM matrix in a range of ABS 10-30 wt% and the blends containing ABS more than 30 wt% showed the elongated structure of ABS phase. The addition of PP-g-MA could improve the interfacial adhesion of POM/ABS blends due to the domain size of ABS phase decreased after adding PP-g-MA. The mechanical properties showed that the impact strength of POM/ABS blends decreased in a range of 10-20 wt% and did not change after 20 wt%. The addition of PP-g-MA did not change the impact strength of POM/ABS blends. The Young’s modulus of POM/ABS blends increased up to 30 wt% of ABS and then decreased. While the blends showed the decrease of tensile strength and percent strain at break with increasing ABS content. The addition of PP-g-MA increased the tensile strength of POM/ABS blends in a range of 30-40 wt% of ABS. The above results indicated that the morphology had an effect on the mechanical properties of polymer blends.