In the present study, a novel crystalline nucleating agent for isotactic polypropylene (PP) comprising the calcium salt of 4‐methyl‐cyclohexane‐1,2‐dicarboxylic acid (MHPA‐Ca) is developed. The performance of the nucleating agent is evaluated by determining the crystallization temperature and isothermal crystallization period of the PP by differential scanning calorimetry, and comparing them with those obtained using the calcium salt of cyclohexane‐1,2‐dicarboxylic acid (HHPA‐Ca), which is one of the most effective nucleating agents for PP. The results demonstrate that the nucleating ability of MHPA‐Ca is much stronger than that of HHPA‐Ca. Consequently, an injection‐molded plate containing MHPA‐Ca has a high degree of chain orientation.