Following the procedure of Mayer et al(6), the lethality of the extracts of B veldkampii and Biophytum shrimp was determined on Artemia salina after 24 hours of exposure of the samples and comparing them relative to the positive control, potassium permanganate. The study reveals maximum mortality took place at a concentration of 10 microgram Iml. The degree of lethality was found to be directly proportional to the concentration of the extracts. The LCso values of the plant extracts were obtained by a plot of percentage of the shrimp nauplii killed against concentration of the extracts and the best-fit line was obtained from regression analysis. The ethanol extract of B veldkampii leaves and B. reinwardtii stems appear to be more effective as it showed an LCso value 3.73 and 2.87ug/ml respectively which can be considered to be comparable to the standard, potassium permanganate(LCso value of 3,920ug/m). The R2 values obtained in the present study were almost close to 1.