Despite many efforts on the synthesis of inorganic nanomaterials with uniform structure and narrow size distribution in a fast and continuous way, it is still a critical challenge in the chemistry research community due to the uncontrollable mass and heat transfer and the harsh experimental conditions of high temperature and pressure. Here we report a droplet- and ionic liquid-assisted microfluidic (DIM) synthesis method, which takes full advantage of both ionic liquids and droplet-assisted microreaction systems, for an ultrafast, mild, and continuous synthesis of various inorganic nanomaterials that takes only tens of minutes rather than days that are usually needed to synthesize. In particular, unaccommodating inorganic nanomaterials that are difficult to produce, such as nanoporous ZSM-S, gamma-A100H, and beta-FeOOH nanorods, were synthesized in only "20 minutes" of reaction time even with simple instrument. The DIM method delineated herein would offer a breakthrough synthetic approach for functional but unaccommodating inorganic nanomaterials in a continuous and mild manner.