Effects of tripalmitin (TP) and low-density polyethylene (LDPE) loading on morphologies and tensile properties of polybutene-1 (PB)/micro fibrous cellulose (MFC)/composite were studied. The scanning electron microscope (SEM) observation showed that the 10 % TP loading brought about good dispersity of the MFC in PB matrix. The TP worked as a good compatibilizer for the composite. The Young's moduli of the PB/TP (10 %)/MFC (10 and 20 %) content were slightly lower than those of the corresponding PB/MFC under 0, 48 and 96 h aging treatments at r. t., and that of the PB/TP (10 %)/MFC (50 %) specifically decreased up to 73 %. The TP loading increased the PB crystal phase transformation rate, and its behavior suggested that there existed TP in the interface between the PB and MFC. The elongation at break values increased up to 281 % of the corresponding PB/MFC ones. The 30 % TP loading little improved the tensile properties of the composite as compared with the 10 % one. The 10 % LDPE loading brought about 5-51 % higher Young's moduli than those of the corresponding PB/MFC without the aging treatment although the composite rapidly became embrittlement by the higher MFC content and aging. It was found that the LDPE loading highly improved the interface strength, in particular, without the aging treatment.