The effect of automobile pollution on floral pigments of Caesalpinia pulcherrima Suotz. and Nerium indicum Miq. was studied. A decrease in Anthocyanin content in flowers of plants growing near Agra-Mumbai Road NH-3 was observed. There was 8 to 35% reduction noted in floral pigments. Nerium indicum flowers were found more affected than Caesalpinia pulcherrima. The reduction in pigments is attributed to auto vehicular pollution load which may adversely affect reproductive biology of plants.