Actin is the structural unit of microfilaments and is an important cytoskeletal protein. Two anti-actin antibodies, mAb3H11 and JLA20, were used to detect actin levels in various cotton plant tissues. Actin levels were estimated using SDS-PAGE and chemiluminescence western blotting techniques. NIH Image software was used to evaluate the blots. Actin levels in 20 day post anthesis cotton fibers appear to be higher than in 10 day post anthesis cotton fibers. Actin levels appear to be higher in tissue from fiber cells compared to tissues from leaves and cotyledons. Roots appear to have a higher level of actin than leaves or cotyledons.