In signature verification using on-line hand written data, we have cleared that the pen inclination data improves the verification rate[1]. However, the influences of intersession variability on the verification rate have not been considered yet. In order to avoid making error caused by mismatch between a test signature and the reference signature, we applied some renewal methods to making the reference. From experimental results using signatures over 9 weeks, a renewal method using authenticated data is effective to maintain high verification rate with 98.5%.