Studies were undertaken to determine the feasibility of using fungicide mixtures more pro fitably against pre-emergence seed-rot or post-emergence seedling blight of groundnut incited by Aspergillus niger. Mixtures of captan + thiram, both at the higher and lower concentrations, were significantly superior to captan + ceresan or thiram + ceresan. It was also observed that ceresan in mixture with captan or thiram did not adversely effect the toxicity of either of the latter two. In other words, captan + ceresan or thiram + ceresan and also thiram + captan were biologically compatible.