Natural protopanaxadiol ginsenosides exhibit low absorption in the human intestine. However, ginsenoside compound K (CK) with 1 conjugated glucose molecule exhibits favorable absorption. The purpose of this study was to compare the pharmacokinetics of ginsenoside CK from a CK fermentation product, CK‐30, and from a red ginseng extract. A randomized, open‐label, 2‐treatment, 2×2 crossover study was conducted. The volunteers were randomly divided into 2 groups. One group received CK‐30, and the other group received 2.94 g of a red ginseng extract. After a 7‐day washout period, the subjects received an alternative treatment for a single dose. The pharmacokinetic parameters, including the maximum plasma concentration (Cmax) and area under the plasma concentration–time curve from time 0 to time of last measurable concentration, were calculated. The median time to reach Cmax of ginsenoside CK after administration of CK‐30 was 3.0 hours, whereas the corresponding value of the red ginseng extract was 10.0 hours. Compared with the red ginseng extract, CK‐30 resulted in a higher systemic exposure to ginsenoside CK, with a 118.3‐fold increase in Cmax and a 135.1‐fold increase in area under the plasma concentration–time curve from time 0 to time of last measurable concentration. The systemic exposure to ginsenoside CK was significantly higher after administration of CK‐30 than red ginseng extract. [ABSTRACT FROM AUTHOR]