The balloon cell nevus is an uncommon variant of melanocytic nevi in which the majority of the proliferation consists of cells demonstrating peculiarly large clear, foamy, or finely vacuolated cytoplasm. The vacuolated cells represent altered nevus cells and upon immunoperoxidase evaluation react positively with several melanocytic markers. Complete excision results in cure. This report describes the second balloon cell nevus of the oral mucosa documented in the English-language literature.