The invention provides an azo type side-chain liquid crystal polyurethane-urea material and a preparation method thereof. The preparation method comprises the following steps: mixing single-ended dihydroxy azo compound (DEH) and double-ended dihydroxy polyethylene glycol (PEG), dissolving with N,N-dimethyl formamide (DMF), performing chain extension with carbamido-containing diisocyanate (HBH) toobtain the azo type side-chain liquid crystal polyurethane-urea. The azo liquid crystal group is positioned on a branched chain, has high utilization rate, can easily form a liquid crystal phase, andhas double excellent characteristics of polyurethane microphase separation and liquid crystal and liquid crystal high polymer molecular ordered arrangement, and the material has liquid crystal property and photochromism based on the polyurethane performance. Furthermore, the polyurethane main chain is a hard segment with an ordered structure, the mechanical performance of polyurethane can be ensured, and the polyurethane has thermoreversible and photoinduced reversible performance of azo liquid crystal and the performance of polyurethane materials.