OBJECTIVE To investigate the screening and evaluation of excipients for soft capsules containing phenylephrine hydrochloride.METHODS HPLC was performed for stability test on.Agilent Zorbax Plus C18 (150 mm×4.6 mm, 5μm) column was used with the mobile phase consisting of mobile phase A:aqueous solution containing 1 g·mL-1 of octanesulfonate sodium and 5 mmol·mL-1 of ammonium acetate, ang mobile phase B:acetonitrile-glacial acetic acid (100:1, V/V).The method was performed by gradient elution.The detection wavelength was 270 nm and column temperature was 30°C.A HPLC was performed to screen excipients on a column of Agilent Zorbax XDB-C18 (150 mm×4.6 mm, 5μm) with the mobile phase consisting of acetonitrile-water (60:40, V/V) at detection wavelength of 355 nm and column temperature of 35°C.RESULTS The aldehyde compounds in polyethylene glycol reacted with the β-arylethylamine of phenylephrine hydrochloride to form isoquinoline, which affected the stability of the drug.Through the determination of aldehyde compounds in polyethylene glycol, the best excipient was from Sasol Germany GmbH.CONCLUSION Soft capsules containing phenylephrine hydrochloride should choose polyethylene glycol with a limit of content less than 5 ppm to carbonyl compounds such as aldehydes.