Antifungal activity of the extracts of plants and marine microalgae against Magnaporthe grisea was investigated. Acetone extracts of promegranate rind, leek seed, and maize husk demonstrated high antifungal activity against M. grisea. MIC (minimum inhibitory concentration) of acetone extracts of promegranate rind, leek seed, and maize husk was 100 ng/ml, 50 µg/ml, and 100 µg/ml, respectively. Ethanol extract of Amphiprora gigantea showed antifungal activity against M. grisea with MIC of 100 µg/ml.