Abstract: Epoxy resins as binders are best known in protective coating field for their excellent corrosion resistance. However, the exterior durability of these resins is severely affected by their poor weathering resistance. The exposure of epoxies to outdoor environment causes chemical reactions within them, which leads to deterioration of their useful properties. A few hours of UV-exposure leads to chalking and discoloration of epoxies, caused as a result of photo-degradation. The present work aims to study the extent to which the color change and yellowing of epoxy caused due to weathering of an aliphatic amine namely, Diethylenetriamine (DETA) cured diglycidyl-ether of bisphenol-A (DGEBA) based epoxy system, when exposed to accelerated weathering conditions, could be lowered by means of a UV-blocking additive, namely nano Zinc oxide (ZnO). A titanium dioxide (TiO2) based white coating with DGEBA epoxy and DETA was formulated and applied on mild steel (MS) panels for the weathering study. The coated panels were exposed in an UVB-weatherometer. Nano zinc oxide particles were synthesized by chemical route and characterized for size, shape and structure. At 2% (by weight) of total coating formulation, nano-ZnO was found to be an effective UV-stabilizer and lowered the degradation in the epoxy-hardener cured system on UVB exposure. The enhanced resistance to color change and yellowing was indicated by lowered color change (dE) and yellowness index values (YI) for the coatings on UVB exposure.