In this article, a novel eggshell/beta-PP bio-composite was prepared and evaluated. First the waste chicken eggshell (ES) was modified by a stingy amount of pimelic acid (PA) through solution method, and then compounded with PP through melt blending method. The crystalline form, mechanical properties, and morphology of the ES/beta-PP composites were studied. The results showed that ES modified by PA was a beta nucleating agent with high efficiency and selectivity, resulting in the maximum K beta value of 0.99 in PP composites. PA modification promoted the dispersion and interfacial bonding of ES in PP. Although the addition of PA-modified ES slightly decreased tensile properties and flexural properties of PP, it increased the impact strength of PP by 228% than that of pure PP. Taking all factors into consideration, the optimal mass ratio of PP/ES/PA composites for reaching optimum mechanical properties should be 100/5/0.000471. Thus, the application of modified ES to prepare ES/beta-PP bio-composites represents a promising way to mitigate environmental pollution and to reduce the cost of polyolefin products. (C) 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012