[Objective] To observe the anti-inflammatory effects of the stems and leaves of Platycodon grandiflorum( Jacq.) A. DC.,and to discuss its anti-inflammatory mechanism. [Methods] ICR mice were randomly divided into model control group,dexamethasone group( 0. 01 g / kg),ethanol extracts groups of P. grandiflorum stems and leaves( 9. 0,4. 5,3. 0 g / kg). Intragastrical administration was carried out once every day with continuous 15 days. On 30 min after final administration,anti-inflammatory effects were researched by observing the increase of blood capillary permeability in mice abdominal cavity induced by acetic acid. SD rats were randomly divided into model control group,dexamethasone group( 0. 01 g / kg),ethanol extracts groups of P. grandiflorum stems and leaves( 9. 0,4. 5,3. 0 g / kg). Intragastrical administration was carried out once every day with continuous 15 days. On 30 min after final administration,anti-inflammatory effects were researched by observing the pleurisy of rats induced by carrageenan. prostaglandins( PGE2),tumor necrosis factor-alpha( TNF-α) and interleukin-1β( IL-1β) contents were detected in exudates,as well as the TNF-α,IL-1β and MDA contents in lung tissues. [Results]Compared with model control group,ethanol extracts groups of P. grandiflorum stems and leaves( 9. 0,4. 5 g / kg) could significantly restrict the increase of blood capillary permeability in mice abdominal cavity induced by acetic acid. Ethanol extracts groups of P. grandiflorum stems and leaves( 9. 0,4. 5g / kg) restricted the increase of PGE2,TNF-α and IL-1β contents in exudates( p <0. 05). 9. 0 g/kg ethanol extracts group of P. grandiflorum stems and leaves restricted the increase of TNF-α,IL-1β and MDA contents in lung tissues( p < 0. 01); and 4. 5 g / kg ethanol extracts group restricted the increase of IL-1β( p < 0. 01). [Conclusions] Ethanol extracts from P. grandiflorum stems and leaves had anti-inflammatory effects; and the anti-inflammatory mechanism might be related to the antioxidation and the production interference of inflammatory mediator. [Objective] To observe the anti-inflammatory effects of the stems and leaves of Platycodon grandiflorum (Jacq.) A. DC., And to discuss its anti-inflammatory mechanism. [Methods] ICR mice were randomly divided into model control group, dexamethasone (0. 01 g / kg), ethanol extract groups of P. grandiflorum stems and leaves (9. 0,4. 5,3. 0 g / kg). Intragastrical administration was carried out once every every day with continuous 15 days. On 30 min after final administration, anti-inflammatory effects were researched by observing the increase of blood capillary permeability in mice abdominal cavity induced by acetic acid. SD rats were randomly divided into model control group, dexamethasone group (0.01 g / kg) , ethanol extract groups of P. grandiflorum stems and leaves (9. 0,4. 5,3. 0 g / kg). Intragastrical administration was carried out once every day with continuous 15 days. On 30 min after final administration, anti- inflammatory effects were researched by observing the pleurisy of rats i nduced by carrageenan. prostaglandins (PGE2), tumor necrosis factor-alpha (TNF-α) and interleukin-1β (IL-1β) contents were detected in exudates, as well as the TNF-α, IL-1β and MDA contents in lung tissues. [Results] Compared with model control group, ethanol extract groups of P. grandiflorum stems and leaves (9. 0,4. 5 g / kg) could significantly restrict the increase of blood capillary permeability in mice abdominal cavity induced by acetic acid .0 g. Kg) restricted the increase of PGE2, TNF-α and IL-1β contents in exudates (p <0. 05). 9. 0 g / kg ethanol extracts group of P. grandiflorum stems and leaves restricted the increase of TNF-α, IL-1β and MDA contents in lung tissues (p <0.01); and 4.5 g / kg ethanol extracts group restricted the increase of IL-1β (p <0.01). [Conclusions] Ethanol extracts from P. grandiflorum stems and leaves had anti-inflammatory effects; and the anti-inflammatory mechanism might b e relatedto the antioxidation and the production interference of inflammatory mediator.