The invention discloses a method for synthesizing a gold-zinc oxide semiconductor composite structure, and relates to preparation of an Au-ZnO nanometer structure. Higher requirements are put forwardby people for an analytical detection means. The ultra-sensitive surface enhanced Raman spectroscopy (SERS) technology is used as an efficient, cheap and powerful analytical detection means because ofnon-destructive and pollution-free fingerprint characteristics to be widely applied in the environmental field. Although noble metals have excellent SERS detection performance, limitations cannot beavoided. With the development of the technology, direct observation of the SERS effect of semiconductor materials has made great progress, and semiconductors gradually become a promising SERS substrate material. However, due to the weak SERS effect, semiconductor materials can not be compared to metals, and the combination of the semiconductor materials and the metals has the effect that the sum of 1 and 1 is greater than 2, so that the collaboration application of the SERS technology, biochemical sensing, gas detection and photocatalytic performance becomes reality.