The effects of a Cr addition and transformation temperature on the strength and work hardening behavior of cold drawn hyper-eutectoid steel wires are investigated in this study. The Cr addition was found to be effective for increasing the tensile strength and work hardening rate,k/(2 λ°)1/2, due to the refinement of the initial interlamellar spacing and the increment of the Hall-Petch parameter. While the work hardening rate,k/(2 λ°)1/2, was significantly influenced by the magnitude of the interlamellar spacing, the Hall-Petch parameter,k, was not affected by the interlamellar spacing. Additionally, the refinement of the interlamellar spacing due to the low transformation temperature and the Cr addition caused an increase of the RA in drawn pearlitic steels.