Blending with low-molecular-weight polyethylene (low-MW PE) is highly effective for improving the processability of ultrahigh-molecular-weight polyethylene (UHMW-PE), but achieving such blending is extremely difficult. In this study, we investigated the blendability of UHMW-PE with low-MW PE via reactor blending. The mixing state was evaluated using a melt drawing method that reflects the molecular entanglement state in the UHMW-PE melt. During melt drawing at 150℃, the UHMW-PE film blended with a small amount of low-MW PE by reactor blending exhibited higher breaking strain than the UHMW-PE film without low-MW PE. In contrast, the breaking strain of the UHMW-PE film blended with low-MW PE by powder mixing was lower than that of the neat UHMW-PE film. These results indicate that reactor blending enables UHMW -PE and low-MW PE to blend at the molecular level. The advantages of reactor blending for blending low-MW PE with UHMW-PE were retained even after dissolution in a solvent. Furthermore, reactor blending also enabled blending of UHMW-PE with low-MW UHMW-PE, resulting in improved melt-drawability. Interestingly, the polymerization sequence of the PE components had a pronounced effect on melt drawing behavior. Reactor-blended powders in which UHMW-PE, the main component, was polymerized first exhibited superior mixing with low-MW PE and more uniform blending. These findings demonstrate the effectiveness of reactor blending for mixing UHMW-PE with low-MW PE and provide important insights for processing UHMW-PE.