Two types of natural rubber (ADS and STR 5L) were used to prepare maleated natural rubber (MNR). Melt rheological properties of MNRs (i.e. MNR-ADS and MNR-STR) and their blends with the same type of natural rubber were quantified. We found that the Mooney viscosities of MNR-ADS/ADS blends were higher than those of MNR-STR/STR 5L blends. The log additive rule was applied to the Mooney viscosity data. Positive deviation blends (PDB) were observed. A power law model was also applied to the shear flow data at a wide range of shear rates. The pseudoplastic (shear-thinning) behavior for all sets of MNR/NR blends were observed with the power law index, n, lower than 1. According to the log additive rule, plots of the consistency index against MNR levels in the blends also indicated positive deviation blends. Shear viscosity data of the blends also confirmed the shear-thinning behavior and the positive deviation blends. From the rheological property point of view, we therefore concluded that the MNR/NR blends were compatible.