Purpose: To observe the enhancement of percutaneous absorption of indapamide through rat abdominal skin using different vehicles, permeation enhancers and organic acids.Methods 2-chamber diffusion cells were adopted as the apparatus for in vitro skin permeation, excised rat abdominal skin as barrier.HPLC method with acetanilide as internal standard was established to determine the content of indapamide in receiver diffusion cell.Results The results obtained indicate that 5% w/w azone, 5% N-methyl-2-pyrrolidone,5% menthol and 5% oleic acid had a strong enhancing effect on the permeation of indapamide and azone exhibited the most potent enhancing effect.All 8 of the organic acids chosen had a potent enhancing effect on the permeation of indapamide across rat abdominal skin.Among the organic acids examined, lactic acid had the greatest enhancing effect.Conclusion.The formulation of an effective transdermal drug delivery system (TDDS) for the delivery of indapamide may be possible.