The sustainable intensification of crop production system requires the efficient use of resources. A 3-year on-farm experiment was conducted to determine the sustainability of plant density for groundnut production in Northern Ghana using the sustainable intensification assessment framework (SIAF). The SIAF allows the assessment of the sustainable intensification potential of the agricultural system in five domains: productivity, economics, environment, human, and social. The experiment was laid out in a strip plot design with six groundnut varieties (early maturity type: Chinese, Yenyewoso, and Samnut 23, and late maturity type: Azivivi, Mani pinta, and Samnut 22) as the horizontal plot factor and four plant densities (22, 15, 11, and 9 plant/m2) as the vertical plot factor. Using the SIAF as a guide, data on grain and fodder yield (productivity), net income and benefit cost ratio (economic), vegetative cover at 30, 40, and 50 days after planting and harvesting and biological nitrogen fixation (environment), calorie and protein production (human), and technology rating by gender (social) were recorded to calculate the sustainability indices of the treatments. The results showed that the sustainability indices for the Yenyewoso and Mani pinta groundnut varieties were above 1 in all the regions, indicating that both groundnut maturity types are sustainable for cultivation in the Northern regions of Ghana. Planting both groundnut maturity types at a density of 22 plant/m2 increased the sustainability index threefold compared with the farmer practice (9 plant/m2) and 79% compared with the 11 and 15 plant/m2. This suggests that planting groundnut at a density of 22 plant/m2 will sustainably intensify groundnut production in Northern Ghana and similar agro-ecologies across West Africa.