Abstract: Objective: An investigation was conducted in Kuru (Latitude 09°44’N, longitude 08°47’E and altitude 1350 m a.s.l.) on the Jos-Plateau, Nigeria to assess the root and vine yields of three landraces and one elite variety of sweet potato (Ipomoea batatas (L.) Lam) as influenced by plant population density and genotype. Materials and Methods: Sweet potato cultivars (Landraces) sourced from both local farmers and the National Roots Crops Research Institute (NRCRI), Umudike, Abia state, Nigeria included Kunkudu, Katsina and Dunku, while TIS.2532.OP.1.13 (An elite variety) served as the check to ensure the purity of the planting material. The parameters tested were the root and top yields, while the plant population densities under investigation consisted of 50,000, 40,000, 33,333 and 28,570 plants ha–1 based on past literature and concurrent studies. These were laid out in a Randomized Complete Block Design (RCBD) consisting of 16 treatments with 3 replications. Data collected were subjected to analysis of variances (ANOVA) according to Snedecor and Cochran, while the Duncan’s new multiple-range test was used to compare the treatment means. Results: Results obtained indicated that the highest and lowest mean root yields were observed in Katsina at 33,333 plants ha–1 (47.89 t ha–1) and Dunku (8.25 t ha–1) landraces, respectively. TIS.2532.OP.1.13 ranked 2nd after Katsina but the difference (p>0.05) was not significant with respect to 50,000 plant population density but showed significant difference (p<0.05) with respect to the other three plant population densities. The mean vine yield showed that landrace Dunku had the highest at 33,333 (59.83 t ha–1) plants ha–1, while the lowest was observed in landrace Katsina (25.22 t ha–1). Conclusion: The study has shown that the optimum plant population density with the most influence on yield parameters was 33,333 plants ha–1 and therefore should guide farmers in making the right choice for maximum yield and breeding potentials either for forage or root production.