This dissertation takes Chinese advertisements as the research subjects to see in what way a quantifiable large number of advertisements with its metaphorical nature and instrumental mission can reflect social cultural change, in specifics, ideology and identity change of China in the last thirty years by combining four methods of research: content analysis, Critical Discourse Analysis, Conceptual Metaphor Analysis and Pictorial Metaphor Analysis. The dissertation goes through the sign or ad interpretation process of linguistic, semiotic and critical analysis of 300 sample illustrated print advertisements collected from popular and award-winning illustrated print advertisements in Chinese media in the three periods of 1980s, 1990s and 2000s respectively. After comparing and contrasting the high frequency key words, advertising appeals and metaphorical expressions and images (categories and groups) appeared in the advertisements of the three periods the following conclusions are made:

First, although advertisements in all the three periods belonged to the commercial public discourse, those in 1980s were inclined towards public discourse without much consideration for specific target groups while those in 1990s and 2000s tended to denote private and personal discourse with clear target groups in mind. While the advertisements in 1980s were characterized largely by the direct informative style, the majority of the advertisements in 1990s manifested a hybridization of both informative and involving styles. The advertisements in 2000s demonstrated strong involving and interacting style.

Second, it can be seen from the shift of advertising appeals from the use of rational appeal to personal appeal that the overall society is moving up the ladder of Maslow's Hierarchy of Needs Analysis from the basic need satisfaction to more social need and personal need satisfaction.

Third, with regard to semiotic image categories used, the result shows the tendency that China is increasingly becoming a male-dominated society with a big increase in using male images from 1980s to 2000s and in particular adult male images. The representational images in the ads show a decline in intimacy but an increase in positional communication. The social setting is the dominant advertising background for all the three periods. Meanwhile with regard to the typical types of metaphorical images that are used as signifieds or secondary subjects to be projected onto the signifiers or primary subjects, there is a decline in using human images as opposed to non-human images. The dominant metaphorical image types used in three periods are in concomitant with the ideology and identity needs of each specific period of time.

Fourth, on the whole the critical metaphor analysis of 300 sample illustrated print advertisements in mainland China from 1979 to 2008 has revealed advertisements during this period, implicitly or explicitly, have served the evolving ruling and dominant ideology very well. The dominant ideologies have changed from political ideology to economic ideology in 1980s, from economic ideology to national ideology in 1990s, and from national ideology to balanced harmonious ideologies in 2000s. The individual consumers have transformed their identities from political self to material social self in 1980s, from material social self to national cultural self in 1990s, and from national cultural self to a individualized my self in 2000s.

The dissertation contributes both theoretically and practically to the advertising research as well as visual culture research. On the one hand it confirms the critical discourse theory that discourse change can reflect socially-constructed reality. On the other hand, it contributes to pictorial metaphor theory by that visual metaphors are deep-rooted in human conceptualization and are cultural-specific.