A rapid, sensitive and reliable capillary electrophoretic (CE) method based on indirect UV absorbance detection has been developed, optimized and applied to the separation and determination of low (mg/1) levels of oxalate in commercial parenteral nutrition preparations. The determination of oxalate requires no extraction, derivatization or other complex pre-analysis steps. The method used chromate as the UV-absorbing background electrolyte and oxalate was detected indirectly at 254 nm. The analysis time for oxalate is just under 7 min per sample with oxalate migrating at approximately 4 min. The method calibration curves were shown to be linear over a minimum of 1.5 orders of magnitude with a limit of detection for oxalate of approximately 240 μg/1. The methods linear dynamic range for oxalate was shown to extend over more than 2.5 orders of magnitude. The final optimized method was used to separate and quantify oxalate in parenteral nutrition solutions that had been submitted to 24-h neonatal phototherapy procedures.