The Thermo Scientific Dionex UltiMate 3000 LC system is applied for the organic impurities analysis of cefdinir. The analysis was performed on a Thermo Scientific Acclaim 120 C18 HPLC column using the method described in the USP 39 monograph. The results obtained for resolution and %RSD met the criteria stated in the USP 39. The resolution between cefdinir and the third peak of cefdinir related compound A was 3.1 (USP criteria of NLT 1.5) and %RSD for cefdinir was 0.1% (USP criteria of NMT 2.0%).