Perovskites (ABX3) have been intensively studied over the past years due to their attractive electronic, optical and optoelectronic properties. Understanding physical insights of making different metal halide perovskite nanocrystals remains in limelight of current research due to their adjustable band gap, high photoluminescence quantum yield and high color purity. In particular, the abundant perovskite raw material can reduce the cost and the production process is simple to speed up the production cycle. With their excellent performance, perovskite LEDs (PeLEDs) will become a strong competitor of inorganic LEDs and organic LEDs in the future. In this talk, we will show how to perform the synthesis of perovskite quantum dots (PeQDs) and apply the synthesized PeQDs to optoelectronic devices.