We developed and validated a new high-performance liquid chromatographic analysis for electrochemically detecting guaiacol and vanillin as important components in vanilla extract. Separation was achieved with Capcell Pak C-18 MG, the potential of the working electrode being set at þ1000 mV. The respective calibration curves for guaiacol and vanillin were linear in the range of 1.60-460 g/L and 5.90-1180 g/L. The respective limits for the quantities of guaiacol and vanillin were 1.60 g/L and 2.36 g/L. The related standard deviations of the intra-and inter-day precision of the retention time and peak area were all less than 4%. The recovery of guaiacol and vanillin was both more than 97%, all of the validation data being within an acceptable range. This analysis method is well suited for the simultaneous and convenient analysis of guaiacol and vanillin in a vanilla extract to evaluate the quality of the vanilla extract.