Chitosan thin films, coated on a quartz plate surface, containing pyrene (Py) and beta-cyclodextrin (beta-CD) units on their surfaces have been designed and prepared as novel sensing materials for nitromethane. Fluorescence studies revealed that the immobilized Py was included in the cavity of its neighbor beta-CD. This structure makes the fluorescence emission of the films could not be quenched by commonly used quenchers, including copper, cobalt and some other transition metal salts, KI and acrylamide. However, addition of nitromethane quenched the emission dramatically. Considering the high selectivity and sensitivity, great reversibility and stability, wide dynamic range and long storage time, it is proposed that these novel films could be applicable to the sensing of nitromethane in some energetic fuels. (C) 2003 Elsevier Science B.V. All rights reserved.