Summary.A simple and accurate reversed phase high-performance liquid chromatography (HPLC) method has been developed for the estimation of uniformity of dosage units, and delivered dose uniformity tests of fluticasone propionate and salmeterol xinafoate in samples obtained during the fine particle mass determination, using C8 Luna (2) 100A 100 × 4.6 mm, 5 micrometer particle size in gradient mode, with mobile phase comprising of buffer solution: 0.6% trifluoroacetic acid solution in watertetrahydrofurane (8:2 v/v) and acetonitrile-methanol (1:1 v/v) in the ratio of 60:40 v/v. The flow rate was 1.5 mL min −1 , and the detection was monitored by ultraviolet (UV) detector at 239 nm and 250 nm. Linearity was observed in the concentration range of 0.025-4.8 μg mL −1 for salmeterol xinafoate and 0.04-32.5 μg mL −1 for fluticasone propionate (R 2 > 0.999). The recovery in the range from 98.2% to 102.7% and relative standard deviation (RSD) ≤ 2.2% demonstrated accuracy and high precision of the method. The quantification limit at an injection volume of 40 μL was 0.04 μg mL −1 for fluticasone propionate and 0.025 μg mL −1 for salmeterol xinafoate. The developed and validated method can be successfully applied for simultaneous quality control of dry powder inhalation products containing salmeterol xinafoate and fluticasone propionate in pharmaceutical industry.