Foamed composites of polypropylene containing bamboo powder were prepared using an injection moulding process. Measurement of density, flexural, tensile and notched impact properties of the prepared composites was carried out. Water absorption of the composites was investigated. The rheological behavior of composites was also investigated by rotary rheometer. The density of microfoamed composites was reduced by about 14%.When the bamboo powder was 50 phr (33.3% by weight), the integrated property was best ; the density was 0.886 g·cm-3 and the flexural, tensile and notched impact strength were 58.72 MPa, 30.86 MPa and 5.246 KJ·m-2 respectively; and the thickness swelling and water absorption were 1.31% and 0.7% after duration of 240 h. The results pointed out the composites showed a flow behavior of pseudoplastic fluid; the storage modulus and loss modulus increased and loss tangent decreased with the increase of bamboo powder content. The composite had a typical shear thinning characteristic and the complex viscosity increased with the content of bamboo powder increased.