Array substrate and preparation method thereof as well as display device

The invention discloses an array substrate and a preparation method thereof as well as a display device. With the adoption of the array substrate and the preparation method thereof as well as the display device, the quantity of mask boards is reduced, the process period is shortened, the production efficiency is improved and the production cost is saved. The preparation method comprises the following steps: preparing a shading layer, a scanning line and a signal line on a substrate through a primary composition technique, wherein the signal line/scanning line is disconnected at the cross position of the scanning line and the signal line; preparing a buffering layer on the substrate prepared in the step above; sequentially preparing a polycrystalline silicon active layer and a grid insulation layer on the substrate prepared in the step above through a secondary composition technique respectively; preparing a grid electrode, a source electrode, a drain electrode, a bonding jumper of the signal line/scanning line and a connection line connected with the grid electrode and the scanning line on the substrate prepared in the step above through the primary composition technique; sequentially preparing an organic insulation layer, a common electrode layer, a passivation layer and a pixel electrode layer on the substrate prepared in the step above through a four-time composition technique respectively.