Arsenic (As) contamination of soil and water is of great concern because As is known to be a carcinogen and mutagen.  Competition between As and P in soils is crucial to understand long-term mobility and transport of As.  This study investigates interactions between P and As (as arsenite and arsenate) in Ultisols with different long-term P management strategies that resulted in 5.13 and 82.7 mg P kg^­‑1 in the low and high P soil, respectively.  Batch experiments were conducted to evaluate the effect of soil P, pH, and As species on As sorption to a highly-weathered Ultisol.  Prior to As sorption experiments, the P sorption capacity of the soil was evaluated.  Phosphate sorption ranged from 50-80% in low P soils and 13-20% in high P soils.  Arsenic concentrations were added from 0 to 13 mmol kg^-1 to both high and low P soils at pH 4.5, 5.5, and 6.5.  Results showed a much greater sorption capacity for arsenate (40-80%) than arsenite (25-50%), which was affected by soil P and pH.  Under high soil P conditions and low pH, arsenate addition resulted in 30-40% P desorption indicating there is some competition for binding between arsenate and soil P.  However, almost no P was desorbed from addition of arsenate to the low P soil or addition of arsenite to either soil.  Highest As sorption potentials were observed for arsenate in low P soils at pH 4.5.  In contrast, arsenite adsorption increased with increasing pH.  Results suggest residual soil P does not have a large impact on As sorption except with arsenate under low pH.