Pests and diseases are among the major biotic constraints in Chilli production which cause serious damage in Chilli production in all the stages of cultivation. Leaf spot of Chilli caused by Alternaria alternata one of the most destructive disease in India. Which are seed borne and reduce the seed germination, yield loss and leads severe economical losses in Chilli crop production which is economically very important. The present book attempts to provide insight leaf spot disease of Chilli and plant extract based management.