Helical substituted polyacetylenes were investigated for inducing enantioselective crystallization of racemic N-(tert-butoxycarbonyl)alanine (BOC-alanine) enantiomers. For this purpose, helical substituted polyacetylenes [(R)-PSA and (S)-PSA)] were dissolved in supersaturated racemic BOC-alanine solutions. Upon cooling the solutions, (R)-PSA preferentially induced BOC-L-alanine to crystallize, while (S)-PSA facilitated the enantioselective crystallization of BOC-D-alanine, according to the characterizations by circular dichroism, XRD, SEM, and optical rotation analyses. As expected, no enantioselective crystallization was observed in such cases: racemic BOC-alanine enantiomers in the absence of optically active helical PSA and racemic BOC-alanine enantiomers in the presence of equal amount of (R)-PSA and (S)-PSA The present study provides the first direct evidence for the role of artificially synthetic helical polymers in inducing efficiently enantioselective crystallization.