Spin-coated films of nickel 1,6,10,15,19,24,28,33-octa-iso-pentyloxy-2,3-naphthalocyanine complex were obtained and characterized by UV-vis absorption spectroscopy. A linear relationship between the absorbance and solution concentration was observed. Low concentration solutions could afford smooth and homogeneous film surfaces as indicated by atomic force microscopy. The film structure was studied by small angle X-ray diffraction. The films were used for NO(2) sensing experiments. The results indicate that the elevation of sensing temperature can shorten the response time and increase recovery ratio and response magnitude of the sensing films. High NO(2) concentration can also shorten response time. (C) 2008 Elsevier B.V. All rights reserved.