In the nucleus of each cell, the DNA molecule is packaged into thread-like structures called chromosomes. Each chromosome is made up of DNA tightly coiled many times around proteins called histone that support its structure. The DNA that makes up chromosomes becomes more tightly packed during cell division and is then visible under a microscope. A Chromosome can be using the identification of species. Each species has a characteristic set of chromosomes with respect to number and organization, different species have different numbers of chromosomes. In this book, the content will cover the technique for mitotic chromosomes preparations from animals. The chromosome staining technique presenting, such as conventional staining, Ag-NOR banding , C-banding, G-banding techniques and fluorescence in situ hybridization. The mitotic chromosomes preparations from animals, such as insect, shrimp, fish, amphibian, reptile, aves and mammal.