(6-(3

(6-(3,4-diaminophenyl)-5-methyl-4,5-dihydropyridazine-3(2H)-one(GTI-A) and p-anisaldehyde (GTI-B)have been highlighted a (GTI's) potential genotoxic impurities (PGIs) of Pimobendan. A sensitive RP-HPLC method was developed and validated for the determination of (6-(3,4-diaminophenyl)-5-methyl-4,5-dihydropyridazine-3(2H)-one and p-anisaldehyde in pimobendan using Zodiac C18 (125 X 4.6mm 5µ) column, with UV Detector. The calibration curves showed good linearity over the concentration range of 0.5μg/mL to 1.5μg/mL with respect to the sample. The correlation coefficient was 0.999. Excellent recoveries of 102 % were obtained at the level of 0.5μg/mL.