Provided is a high-purity crystal form of 2-(3,5-dimethyl-1H-pyrazol-1-yl)-5-methylphenol that is stable during storage, industrial production, and distribution. Also provided is a method for producing the crystal form. Provided are stable, high-purity crystals of 2-(3,5-dimethyl-1H-pyrazol-1-yl)-5-methylphenol and a method for producing the crystals by using a boron compound.