［Purpose］In order to make up for the limited recognizability of the single color technology topic map after clustering, enhance the expressiveness of the technology topic map and enrich the drawing methods of technology topic map and the selection range of software tools for  analysts.[Method］A visualization method of technology topic map with clusters is proposed. The layout algorithm is applied to layout the topic words, and the pixel density function, class density function and color intensity function are established. According to the class density and color intensity value, the color rendering is carried out, and the clustering technology topic map is obtained. [Results] The method is embedded in itginsight software，which is a text mining and visualization software tool, and applied to the case analysis of quantum cryptography communication patent data, the results show that the method is simple and effective.