Printronix, Inc. uses scanner-based image systems to perform print quality measurements for line-matrix printers. The size of the image samples and image definitions requirement make commercial scanners convenient to use. The scanner-based image quality measurement system has been utilized to increase repeatability and accuracy. Printronix has developed software package, based upon MATLAB, which permits the use of standardized algorithms to interpret the data. The PC based analysis tool can process data efficiently and yield more accurate results. Additionally, the new method can provide in-depth information on individual attributes that contribute to the overall visual perception of image quality. This paper presents the measurement and analysis methods of determining the quality of prints generated by line matrix printers. Several key image quality aspects such as dot density, dot size, dot uniformity, dot positioning, and ink smearing measurement, are discussed in the paper.