The invention publishes a kind of drug complex with cholagogue and lithontriptic effect and its preparation method; the invention also publishes a kind of quality-control method of a kind of drug complex soft capsule. The invention drug complex is composed by the main materials of mint oil and herit oil. The aforementioned drug is mixed uniformly according to certain proportion, and can be added into conventional accessories to prepare into clinically accepted forms of drug, such as pill, tablet, orally-taken liquid preparation, capsule, granule et al. To control the drug quality according to the quality-control method of the soft-capsule-form drug publicized in the invention, good product stability and high repeatability can be acquired; The invention drug complex has distinct cholagogue, lithontriptic, anti-inflammation, analgesic effect through the pharmacological experiment.