In this work, an attempt was made to prepare dynamically cured TPNRs based on blends of MNR and high-density polyethylene (HDPE) via a dynamic vulcanization process using a phenolic resin curing system. Influences of three types of blend compatibilizer on the properties of the TPVs were investigated. Mechanical, morphological and dynamic properties were then studied. Our main aim was to determine the proper type and loading amount of blend compatibilizer and to produce a two-phase system with high strength and other important properties.