Abstract: The unique asymmetry of chemistry or composition of external and internal surface for Janus cage allows it to be used as a special microcontainer for separation, enrichment, transport and restricted reactions. To some extent, large aperture of cage can enhance the material transport efficiency between microcontainer and the environment. A two-step method to prepare magnetic organic/inorganic composite Janus cages with large aperture and pH responsiveness was introduced in this paper. Firstly, a magnetic inorganic Janus cage with a well-supported shell and adjustable aperture was prepared by the sol-gel of silane coupling agents and microphase separation of two surfactants at the interface. Then pH-responsive polymer poly diethylaminoethyl methacrylate (PDEAEMA) was grafted on the interior surface of inorganic Janus cage by Cu-mediated controlled radical polymerization to obtain functional Janus composite cages. SEM, TEM, FTIR and TGA were performed on composite cages. The size of cages is about 1-3 μm, with tunable pore size from 40 nm to 1 μm. The proportion of polymer in the composite cages is 41.7wt%. Controlled absorption and release of oil and oriented transport of substance can be achieved by changing pH and magnetic manipulation respectively with these composite Janus cages, which means it is promising for drug loading and targeted release in vivo.