The invention discloses an in-vitro construction method for simulating a blood brain barrier through human brain microangiogenesis. The method comprises the following steps: preparing human brain microvascular endothelial cell suspension and human astrocyte suspension, and preparing fibrinogen mother liquor and thrombin mother liquor; mixing the endothelial cell suspension, the astrocyte suspension, a DMEM (Dulbecco's Modified Eagle Medium) medium, the fibrinogen mother liquor and the thrombin mother liquor, and preparing a mixed cell gel solution; injecting the mixed cell gel solution into amicro-fluidic chip, performing thermostatic incubation to gelation, adding an endothelial growth medium into the micro-fluidic chip, and constructing a 3D cell culture chip; performing continuous culture on the 3D cell culture chip, and enabling the endothelial cells and astrocyte to grow into a brain microvascular network structure, namely correspondingly producing the simulated blood brain barrier. According to the technical scheme provided by the invention, the in-vitro model of the blood brain barrier is successfully constructed, and the characteristics of the blood brain barrier are clearly and accurately reflected.