This chapter describes the flow of a chromosome analysis using an IBAS (Zeiss/Kontron) image analyzer. NIH Image is constructed and distributed by the National Institute of Health, USA. NIH Image is obtained via the Internet. The application of image technology to human chromosome research began in the 1960s as diagnostic demands increased. Automatic detection of good chromosomal spreads and subsequent automatic karyotyping to detect chromosomal aberration were objectives in clinical cytology. The chapter also describes a basic image analysis procedure for plant chromosomes to obtain the density distribution of a chromatid, or condensation pattern, as an example of digital chromosome image analysis. Three essential attributes of imaging methods are worth considering. First of all, manipulation of an image by any imaging method basically reduces the information. Second, standards for image manipulation procedures and for judging the results. Third, and somewhat surprisingly, the optimal conditions for image analysis and for human vision are sometimes different.