Immunostaining is a powerful technique for visualizing tissue morphology and protein expression patterns, but in non-model organisms, it may be impeded by a lack of established protocols. Here, we present a protocol for whole-mount immunostaining of termite brains that we applied to the termite Reticulitermes flavipes. We describe steps for brain dissection, fixation, staining, and mounting. This approach generates stained termite brains that can be visualized through confocal microscopy and can potentially be adjusted to suit other insect species. For complete details on the use and execution of this protocol, please refer to Merchant and Zhou. 1 .