In this work, new ethylene gas sensor was developed on the basis of portable bacterial cellulose (BC) nanofiber film doped with KMnO 4 (K-BC). The relationship between the concentration of KMnO 4 (8 × 10 −3 , 8 × 10 −4 , and 8 × 10 −5 mol L −1 ) and the optical and morphological properties of ethylene sensor was investigated. The Fourier-transform infrared results showed that some new interactions have occurred between BC membrane and KMnO 4 . The significant reduction in the relative intensity of the characteristic X-ray diffraction peak of BC in the doped films clearly indicates that the crystalline fraction decreases as a result of KMnO 4 addition. The fabricated K-BC was used for determination of ethylene concentration. The color, clarity, and absorbance of film at different concentrations of ethylene (10-2000 μg mL −1 ) were determined by spectrophotometer. Moisture absorption and water vapor permeability of BC were increased by the addition of KMnO 4 . Finally, the ethylene optical sensor was used for detection and determination of ethylene concentration in the bunch banana packages.