Cotton (Gossypium spp.) seed coat quality was tested using an Instron Instrument in a double shear test. Five cotton genotypes were examined with five seed parameters significantly different among genotypes. These parameters were energy to breakpoint, displacement, load, weight, and minimum diameter. Step wise regressions failed to identify seed parameters that contribute to seed coat quality. Physical seed parameters examined were longest length and largest diameter, shortest length and minimum diameter, longitudinal cross-section, and mass. Eleven percent of the variability could be accounted by mass and length when load was the dependent variable; no other parameters contributed significantly to load. Brittle seed coat requires a shorter displacement before breaking and less force to break the seed coat. In a ginning experiment a correlation was found between number of seed coat fragments and seed shear strength.