Efficacies of both the ethanolic and aqueous extracts of Calotropis gigantea, R. Br. (Ascelepiadaceae), Physalis angulata L., Aframomum melegueta K. Schum, Piper guineense Schum & Thonn, Delonix regia (Bojer ex Hook.) Raf., Xylopia aethiopica (Dunal) A. Rich, Blighia sapida Koeing, Tetrapluera tetraptera, Jatropha curcas Linn. and Raphia vinifera were tested on second instar larvae of Anopheles mosquito for 24hours. The LC50 and LC95 conducted showed that the ethanolic extracts of P. guineense seeds emerged the most active with 0.028mg/ml while the aqueous extracts of D. regia (20mg/ml) seeds, J. curcas (18.25mg/ml) seeds and R. vinifera (<20mg/ml) seeds were the least active. For the mean mortality graph against concentration, the Sigmoid (S-shape) pattern was obeyed in which case; the mean mortality varied directly with concentration.