This paper studies the dynamic relationship among media supervision, inefficient investment and corporate value based on violations of the manufacturing listed companies subject to regulatory penalties from 2010 to 2012. The results show that: the listed companies are mostly under-investment; the media supervision has significantly negative correlation with the inefficient investment, the media supervision can decrease the inefficient investment obviously; no matter in state-owned companies or in non-state-owned companies, the media supervision can decrease the inefficient investment, and it can restrain the inefficient investment of non-state-owned companies more obviously; the media supervision can restrain the inefficient investment to damage the corporate value, and so to protect the interests of shareholders.