The present invention relates to a method for producing clinically effective quantities of human adipose tissue-derived stromal cells for treating fistulas and a composition made with the same. The method of the present invention can efficiently produce clinically effective number of adipose tissue-derived stromal cells within a short period by improving conventional standard culturing methods. The adipose stem cells composition containing the adipose tissue-derived stromal cells obtained by the method of the present invention exhibit superior multipotency and immunomodulatory activity over those of a cell composition produced by conventional methods, and thus is more suitable for treating fistulas. The cell composition of the present invention has excellent clinical usages especially since immune response is suppressed in allogenic adipose-derived stem cells.