Despite the significant enhancements in material properties such as carrier mobility, few attempts have been made to print organic integrated circuits (ICs). The relatively large size of printed features (typically 10 μm – 100 μm) have limited the implementation of organic ICs with reasonable transistor densities. To overcome the limitation, we introduce three-dimensional (3D) integration of inkjet-printed organic transistors and circuits. We fabricated a p-type organic field-effect transistor that is inkjet-printed on top of an n-type organic field-effect transistor with a shared gate joining the two transistors. Based on the common-gate transistor-on-transistor structure, a complementary inverter array is fabricated with a high static noise margin and reliable characteristics. We have further developed 3D integration of a dual-gate NAND technology fabricated by printing technique with a demonstration of flexible logic circuits. The vertical stacking of independent-gate controlled dual gate transistors offers enhanced on-current, lowered sub-threshold swing, increased device stability and density. The present study fulfills the essential requirements for the fabrication of organic printed complex ICs, and the findings can be applied to realize more complex digital/analogue ICs and intelligent devices