Micellar electrokinetic capillary chromatography (MECC) with on-column UV detection at 214 nm, was used to detect and determine platinum(II) in the presence of Rh(III), Ru(III), Os(III) and Ir(III) in acidic medium (HCl+KCl, pH=3.0). Under an applied voltage of 15 KV, platinum(II) tetrachloride (PtCl2−4) was separated and detected in less than 4 min. A cathodic injection and anodic detection scheme was used. The electroosmotic flow was reversed by a cationic surfactant (CTMAB) and the analysis time was shortened. The linear calibration range is 0.2–40 μg/ml. The detection limit is 0.2 μg/ml. The method is most useful for samples digested in HCl/HNO3. The method is simple, rapid and highly selective.