Abstract: In this study, two dual sweet potato (Ipomoea batatas L.) cultivars (main plots) viz., SPN/0 and SP/93/23, differing in shoot morphology were subjected to vines and leaf harvests (sub-plots) under field conditions at Sokoine University of Agriculture, Horticultural Unit, Morogoro, Tanzania. The treatments were arranged in a split plot arrangement in RCBD using three replications during the 2003/2004 cropping season. The purpose of the study was to evaluate the effect of removing vines and leaves on yield of marketable roots and leaves. Vines and edible leaves were progressively removed during the growing season. The control treatments consisted of single final removing of vines. Vines and leaves removal treatments were imposed monthly and bi-weekly commencing at 40 and 54 days from planting, respectively. Varieties differed in all the variables tested except average marketable root diameter. SPN/0 was characteristically superior in all the variables including marketable root yield. SPN/0 variety gave a relatively higher final yield of 12.2 t ha-1 fresh marketable roots, over the SP/93/23 variety, which gave 2.9 t ha-1. Among all four subplot treatments tested, there was no significant difference on number of slender roots, number of marketable roots, average marketable roots length, average marketable root diameter, total weight of vines and leaves and marketable root yield. However, significant difference (p<=0.05) among treatments of vines and leaf removal were obtained only on weight of fresh vines and leaves. Removing vines and leaves once per month starting 40 days after planting gave the highest weight of fresh vines and leaves of 6.1 t ha-1. The control treatment gave 11.6 t ha-1 of fresh marketable roots, which out yielded all the other three treatments. Results indicate that the yield decrease depends on time of starting topping and frequency of topping. Continuous removal of vines and leaves, starting at early stage reduced root yield though not significantly. The none topping of sweet potato gave relatively higher yield of fresh root tuber compared with other treatments. Removal of vines and leaves once per month starting 54 DAP is recommended for optimizing aerial fresh weight and marketable root yield.