In a developmental study on the expression of heat shock protein 108 (HSP108) mRNA in the chicken retina, we found different spatial and temporal expressions of HSP108 mRNA in each retinal layer. While intense HSP108 signals were found in the retina neuroblast layer at embryonic day 5 (E5), the ganglion cell population (GC), inner nuclear layer (IN) and pigment epithelium (PE) showed HSP108 expression at E9. At E14, HSP108 signals were reduced versus the previous stages even though signals were still detected in the GC, the IN, the outer nuclear layer and the PE. HSP108 signals were still detectable at the E21 stage, although each retinal layer showed a much differentiated morphology and diminished signal intensity. These results suggest that HSP108 expression might be developmentally regulated throughout eye organogenesis and that it plays a role in ocular development.