Conventional protocols of fluorescence in situ hybridization (FISH) typically require the use of mitotic metaphase chromosomes obtained from somatic cells. In contrast, we present a protocol for FISH on giant lampbrush chromosomes (LBCs), which represent meiotic diplotene bivalents from growing egg cells and are found in many species, including amphibians, reptiles, fish, and birds. Due to their unique organization, LBCs can serve as a relevant model for high-resolution molecular cytogenetic and cytological studies. In this chapter, we describe the basic protocol for FISH on LBCs, which can be used to detect both DNA and nascent RNA transcript targets. In addition, important variations of the hybridization protocol and examples of their application are presented.