There is little information on the single and combined effects of reniform nematodes and silverleaf whiteflies on cottonseed quality. Whiteflies can be a serious pest in the Lower Rio Grande Valley (LRGV) of Texas, Arizona, and California, whereas, reniform nematodes are present in the LRGV and many other cotton producing areas in the Mid South and Southeast. Investigations were conducted to determine the singular and combined effects of the reniform nematode and silverleaf whitefly on seed quality. Field studies indicated that under high whitefly infestations seed quality could be significantly reduced. Seed quality was reduced but to a lesser extent by reniform nematodes. The investigations indicated that the presence of both pests could result in an increased reduction of reduce seed quality. It appears that seed produced under these constraints may require greater care in processing.