The deep integration of information technology and education and teaching under the background of "Internet +" is the general trend. Online teaching based on information technology is transforming to the new normal. Taking the main course of architecture major "Campus Architecture Design" as the empirical research object, based on the relevant theories of blended-learning and integrated the teaching characteristics of architecture design course and the advantages of online and offline teaching, the exploration and practice of multi-blended online teaching design has been carried out from five aspects by the high-quality online teaching platform: curriculum objectives, teaching tasks, teaching organization, teaching content and teaching evaluation. The analysis of practical results shows that online teaching under the multi-blended concept can effectively stimulate students' learning interest, promote the construction of systematic architecture knowledge and improve the ability of innovative design thinking, which can provide practical references for architecture design online teaching and even other design disciplines in the post-epidemic era. At the same time, it plays a positive role in promoting the first-class undergraduate courses construction of architecture major.