In this work, octamethylenedicarboxylic dibenzoylhydrazide (OD) with intense hydrogen bonds in its molecules, was chosen as the nucleating agent of polylactide (PLLA). As the specificity and directionality of hydrogen bonds, OD can self-assemble into different superstructures like dendritic or fibrillar superstructures in the PLLA melt. Most interesting, we found that the self-assemble behaviors of OD depends on its concentration and external temperature, and the dendritic or fibrillar superstructures can serve as nucleation templates to induce the crystallization of PLLA on their surface, resulting in a large enhancement in crystallization rate. Moreover, we successfully obtained the PLLA crystalline morphology with dendritic, shish kebab and sunflower-like structure, respectively. The weak interaction between PLLA and OD molecules, which is proven by the two-dimension correlation spectra, can change the conformation distribution of PLLA molecules and play key role in the crystallization mechanism of the PLLA/OD system. Keywords: Self-assemble, nucleating agent, weak interaction, PLLA, crystallization, Two-dimension correlation spectra