The pharmacokinetic parameters of aristolochic acid-Ⅰ (AA-Ⅰ) and -Ⅱ (AA-Ⅱ) in rat serum after intragastrical administration of the crude drug powders of Radix Aristolochiae (RA) and Muskone containing equal amounts of RA were compared. The pharmacokinetic profiles of AA-Ⅰ and AA-Ⅱ could be fitted with a two-compartment model The elimination half time (T1/2β) of AA-Ⅰ in Muskone was 1573.2 min and that of AA-Ⅰ in RA was 475.8 min; T1/2β of AA-Ⅱ in Muskone was 2344.8 min and that of AA-Ⅱ in RA was 427.8 rain. The area under the concentration-time curve (AUC) of AA-Ⅰ in Muskone was 13.07 μg/h/mL and that of AA-Ⅰ in RA was 3.86 μg/h/mL; AUC of AA-Ⅱ in Muskone was 67.67 μg/h/mL and that of AA-Ⅱ in RA was 23.93 μg/h/mL. The bioavailabilities of AA-Ⅰ and AA-Ⅱ in Muskone were markedly increased compared with that in RA based on the elimination half-time and A UC values.