The use of cultivars that gin faster and require lower net ginning energy have been suggested to improve ginning efficiency. The objectives of this study were to investigate the relationships of lint yield and fiber quality with ginning rate and net ginning energy, and also determine the effects of semi-naked seed, fuzzy seed, okra leaf, and the presence or absence of nectaries on ginning rate and net ginning energy. Thirteen cotton genotypes were evaluated in a randomized complete block design with four replications for ginning rate, net ginning energy, fuzz percentage, lint yield, and fiber quality at Stoneville, MS across four environments during 2013 and 2014. Ginning rate was positively related to lint yield (0.27, p < 0.001***), fiber strength (0.22, p < 0.01**), and fiber length (0.41, p < 0.001***). Ginning rate, however, was negatively correlated with net ginning energy (-0.28, p < 0.001***) fuzz percent (-0.06, ns), and micronaire (-0.38, p < 0.001***). Higher lint yield appeared to be associated with higher net ginning energy. Net ginning energy was positively correlated with fiber length (0.26, p < 0.001***), fiber strength (0.23, p < 0.001***) and fuzz percent (0.50, p < 0.001***). The okra-leaf group had higher ginning rate than the normal-leaf group (p < 0.05*). The semi-naked-seed group had higher ginning rate than the fuzzy-seeded group (p < 0.05*). The fuzzy-seeded group required higher net energy to gin. Cotton breeders should consider these relationships before embarking on a program to improve ginning efficiency.