With content analysis of the presentation of ‘migrant workers dun for default laborage’ issue by fve traditional mainstream newspapers in China, this research explores the reporting features and operational logic of mainstream media on this kind of subject which is of the underpriviledged’s survival foundation. It fnds out that the sample media take continuing report of this issue and discuss it from the various perspective of its causes, countermeasures, referred subjects, etc. The newspapers demonstrate concerns on migrant workers’ plights with sympathy and support for their interest expression. They hold diverse attitudes towards the stake holders as well. However, the newspapers didn’t reveal this social problem timely and their report of the issue is ‘seasonal’, i.e., they gave more attention on it around Spring Festival than at other period of time. Moreover, the newspapers conceal the con?icts and the profound problems and show the administrative achievement of authoritative parts by selectively presenting facts. In a word, it demonstrates the characteristic of the role played by traditional mainstream media in the interest expression of the underpriviledged from one side, namely expresser with ambiguous attitude, not representative. At the same time, the research also reminds us that it is necessary to distinguish the form and the essence of the expression when discussing the ‘interest expression mechanism of mass media’as one of the underpreviled’s interest expression mechanism.