Planting density can influence the growth and potential yield of grain sorghum systems, particularly in resource-limited environments. Therefore, documenting the sorghum’s response to different planting densities is essential for understanding crop behavior in relation to optimal yields. A study was conducted in Lahoma and Perkins, Oklahoma, in 2019 and 2020 to assess the impact of varying planting densities and within-row planting in-row gaps. Planting density varied from 43,225 to 223,500 plants ha⁻¹. Three additional treatments were implemented at 148,000 plants ha⁻¹ with 0.3, 0.6, and 0.9 m gaps. An increase in plant density resulted in higher yields at Lahoma in 2019. However, at Perkins in 2019 and 2020, yields were optimized at 148,000 and 111,000 plants ha⁻¹, respectively, and decreased as planting densities diminished. In-row gaps of 0.3 and 0.6 m did not significantly affect yields across all site-years; however, at Perkins, the 0.9 m gap significantly reduced yields compared to stands without gaps in both years. Overall, a direct relationship was observed between sorghum yields and planting density. Further evaluation of in-row gaps and how planting management should be adjusted is warranted based on the presented information.