Borrowing the term of “supply-side reform” in economics, this paper discusses the new problems in the teaching of ideological and political courses in colleges and universities in the new era and the countermeasures to solve these problems from the perspective of “supply-side reform,” i.e., the reform from the side of the teacher. This paper points out that there are problems in the overall quality, teaching philosophy, course content and teaching methods of the ideological and political course teachers. Specifically, the overall quality of the ideological and political course teachers needs to be further improved, the teaching philosophy needs to be further changed, the course content needs to be enriched and diversified, and the teaching methods need to be further innovated. To solve these new problems, this paper puts forward some countermeasures to improve it from many aspects, aiming at providing some reference for the teaching of ideological and political courses in colleges and universities, improving the teaching quality of ideological and political courses, and fulfilling the mission of educating people for the Party and the country.