OBJECTIVE To study the effects of self-assembled nanoparticles from Shaoy ao gancao decoction （SGD-SAN）on the in vitro release and intestinal absorption of the main components of Glycyrrhiza uralensis . METHODS Gancao single decoction （GSD），Shaoyao single decoction （SSD），mixed suspension of Shaoyao and Gancao single decoction （MSSGD）and SGD （i.e. Shaoyao-Gancao decoction ）were prepared ，and SAN was characterized. HPLC method was adopted to determine the contents of 7 main components （liquiritin apioside ， liquiritin， isoliquiritin apioside ， isoliquiritin， liquiritigenin， glycyrrhizic acid ， isoliquiritigenin）in G. uralensis . The dialysis bag method was used to investigate the effects of the formation of SGD-SAN on in vitro release of 7 main components in G. uralensis with pH 1.2 HCl solution and pH 6.8 phosphate buffered solution （PBS）as release media. Single-pass intestinal perfusion study was performed to investigate the effects of the formation of SGD-SAN on the intestinal absorption of 7 main components from G. uralensis . RESULTS SAN with particle size of 200-300 nm and polydispersity index of 0.3-0.5 was found in GSD ，MSSGD and SGD. GSD-SAN and MSSGD-SAN were in rod shape while SGD-SAN was irregularly spherical under transmission electron microscope. The results of in vitro release study showed that the formation of SGD-SAN could significantly increase in vitro release of liquiritigenin ，isoliquiritigenin and glycyrrhizic acid ，and had no effect on other components of G. uralensis in pH 1.2 HCl solution. The formation of SGD-SAN also had no effect on the release of each component from G. uralensis in pH 6.8 PBS. The results of intestinal perfusion experiments showed that the formation of SGD-SAN could significantly promote the absorption of each component from G. uralensis in the ileum. CONCLUSIONS- The formation of SGD-SAN significantly improves the in vitro release of poorly soluble components from G. uralensis and promotes the intestinal absorption of main components from G. uralensis ，which is the physical structure basis for the compatibility and synergy of Paeonia lactiflora and G. uralensis .