An image analysis procedure was developed to quantify morphological characteristics of convolutions in individual cotton fibers without pre-tensioning or orientation requirements. The image of each fiber was captured by a PC-based color imaging system using a conventional microscope. Ends of individual cotton fibers were glued on a microscope slide without any tension or straightening. A modified watershed technique was implemented to identify individual convolution segments, which were defined as sections of the fiber bordered by two neighboring convolutions. Length, area and perimeter of each convolution segment were measured directly from the image. Average width, shape factor and number of convolution segments in mm were calculated from the measured parameters. The performance of the image analysis algorithm was compared with visual inspection for number and position of convolution segments in three different varieties of cotton. The image analysis results agreed with visual inspection in 89.6% of the tested images.