Cellular stress causes DNA strand breaks that are typically repaired to maintain homeostasis and regulate cell fate. However, unrepaired DNA breaks can be lethal, leading to cell death. Here, we present a protocol to study DNA strand breaks in Drosophila during development and apoptosis using in situ nick translation. We describe the steps for labeling DNA strand breaks using digoxigenin (DIG)-labeled nucleotide (DIG-11-dUTP) and visualizing them with anti-DIG immunostaining. We then detail procedures for mounting, imaging, and analysis. For complete details on the use and execution of this protocol, please refer to Maurya et al.(1) and Rigby et al.(2).