‘Spancross’, ‘Florunner’, and ‘Florigiant’ cultivars were used to determine the relationship between arginine maturity index (AMI) and other traits in peanut (Arachis hypogaea L.). Samples were taken weekly beginning 73 days after planting in 1973 and biweekly beginning 77 days after planting in 1974. AMI-1 was measured on fresh fruit and AMI-2 was measured on dry seed. The relationship between these two characters was greater than r = 0.85 in each cultivar tested. Both AMI-1 and AMI-2 were positively correlated to percent of other kernels and negatively correlated to pod yield, and percentages of total sound mature kernels, total kernels, dry matter, and mature seed. Among these correlations AMI-pod yield was weakest, whereas AMI-percent of total sound mature kernels was strongest. The quadratic polynomial, Y = a + bx + cx², was used to fit the distribution curve for each trait. Florunner and Florigiant appeared to have similar patterns in all traits except percent of mature seed, but they differed from Spancross in these traits.