Abstract: Three types of calcium pimelate, D-CaPi, N-CaPi and S-CaPi, were prepared by a meta-decomposition reaction, a neutralization reaction and physical compounding of pimelic acid with calcium stearate, respectively, and the effect of different types of calcium pimelate on crystallization and melting behaviors of polypropylene (PP) were investigated. The chemical structure of calcium pimelate was confirmed by Fourier-transform infrared spectroscopy, and the crystallization and melting characteristics of PP/calcium pimelate compounds were determined by differential scanning calorimetry. The results indicated that these three types of calcium pimelate exhibited a nucleation capability for the crystallization of PP, which leads to an increase in crystallization temperature by 4.9 ℃ for PP/D-CaPi and PP/N-CaPi compounds and 6.5 ℃ for PP/S-CaPi compound. Moreover, S-CaPi was found much easier to induce β-form crystals for PP than D-CaPi and N-CaPi, and it could result in the formation of 84.5 % β-crystals for PP.