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.