Objective To investigate the effect of Platycodon grandiflorum polysaccharides (PGP) on the pharmacokinetic parameters of platycodin-D (PD) in rats and to provide experimental data for clinical application of Platycodon grandiflorum. Methods Twenty-four Sprague-Dawley rats were randomly divided into PD group and PD+PGP groups with low, medium, and high doses of PGP (PD-PGP-L, PD-PGP-M, and PD-PGP-H groups). After oral administration, blood was taken from the eye canthus at each time point, and the plasma concentration of PD was determined by high-performance liquid chromatography. Pharmacokinetic parameters were fitted using DAS 2.1 software. Results Compared with the PD group, PD in the PD-PGP-L, PD-PGP-M, and PD-PGP-H groups had significantly reduced time to peak (P<0.05) and significantly increased peak concentration (P<0.05) and area under the concentration-time curve (P<0.05).Conclusion PGP can significantly change the pharmacokinetic parameters of PD after oral administration.