Objective: To compare the pharmacokinetics and bioavailability between ambroxol hydrochloride oral solution and tablet. Methods: Volunteers were given oral solution or tablet with a single oral dose of 90 mg ambroxol hydrochloride in a randomized crossover study. The plasma concentrations of ambroxol were determined by HPLC method. Three factors analysis of variance and two one-side t test were adopted in the evaluation of the area under plasma drug concentrations-time curve (AUC ). Results: The maximum plasma concentration(cmax) of ambroxol oral solution and tablet were(169.03±23.42) and (163.17 ± 23.41) ng/ml; the time to reach cmax (tmax) were (1.20±0.22) and (1.44±0.23) h; elimination half-life(t1/2β) were(7.07±1.54) and (7.97 ± 1.17) h, AUC were (1 287.13±250.84) and (1 317.85 ± 151.31) h*ng/ml, respectively. Conclusion: The two preparations of ambroxol are of the same bioavailability. The relative bioavailability of oral solution of ambroxol is (97.61±15.65)%.