We describe a very simple method to immunostain Drosophila mitotic chromosomes for spindle checkpoint proteins and kinetochore components. By using appropriate primary antibodies, this procedure allowed us to detect Zw10, Zwilch, Cenp-C, Cenp-meta and BubR1 on kinetochores of larval brain chromosomes. However, the same method can be used for detecting also structural components of chromosomes (our unpublished results).