This article reports a validated stability-indicating capillary electrophoresis method using a photo- diode array detector at 220nm for the determination of cinacalcet hydrochloride. The best electrophoretic separation between the analyte and internal standard (lamotrigine) was achieved within 5min in a deactivated fused silica capillary (55cm effective length�75lm internal diameter) maintained at 24�C using a background electrolyte solution consisted of phosphate buffer (50mM, pH 6.4):methanol (95:5, v=v) at a separation voltage of 30kV. The linear range of the method was 0.5–30lg=mL (r¼0.9999) with limits of detection and quantitation of 0.1 and 0.5lg=mL, respectively. The assay precision and accuracy were favorable as the relative standard deviations did not exceed 1.09%, and the recovery values were 98.99–100.33�0.19–1.09%. The induced degradation products, when any, did not interfere with the detection of analyte. The proposed method was successfully applied for the determination of cinacalcet hydrochloride in bulk and pharmaceutical formulations; the percentage recovery values were 98.16–102.00�0.24–1.08%. The results demonstrated the value of the method.