The present invention provides a sustained-release aromatic, characterized in that the aromatic comprises at least one perfume derivative as an active component selected from glycosides of perfumes, phosphoric acid ester derivatives of perfumes, amino acid derivatives of perfumes and carboxylic acid derivatives of perfumes, and contains no enzyme or acid which decomposes the perfume derivative, wherein the perfume derivative is decomposed by bacteria usually present on the skin or yeast to release a perfume component to exhibit aroma. The present invention also provides a method for the detection of micro-organisms using the aforesaid sustained-release aromatic. As the sustained-release aromatic of the present invention releases a perfume component only when it is decomposed by micro-organisms such as bacteria usually present on the skin or yeast, the amount of perfumes to be used can be extremely reduced. The sustained-release aromatic of the present invention is also excellent in keeping aroma. The stability with the passage of time of the sustained-release aromatic of the present invention is much better than that of the prior art because the perfume component is contained in the form of derivative. The sustained-release aromatic of the present invention is useful for applications on the skin, head skin or hair of human beings or animals, on clothes, or in drinks and foods, or as an indicator for detecting micro-organisms.