Extension marketing theory is an essential part of Extension engineering theory, and is an important application of Extenics in marketing. As the combination of extension theory and marketing theory, it is an esstential complement to marketing research. Chinese scholars Cai Wen and Yang Chunyan (2000) firstly proposed Extension marketing theory at the end of the 20th century. Its core theory is to solve the contradictory problems in marketing processes with extension tools, such as extensibility, extension transformation, extension set and et al. The significant difference between extension marketing and traditional marketing is the innovative essential characteristics of extension marketing, and the innovation results include new products, new markets, new available resources, new plans, and new enterprises. At present, extension marketing research mainly includes five parts: product extension innovation, extension market, extension resources, innovation enterprise and extension marketing planning.

(1)Product extension innovation

It uses affair-element to formalize the demands of products, research the extensibility of demands, and propose the formalization analysis method of demands. It can provide the formalization creation thought of new product based on demands, and facilitate product development teams to construct new product conception. We can study the rules of developing products by analyzing their extensibility, and give full concept of products according to their conjugacy. We classify products with satisfaction, so as to make different innovative plans for different products. The divergence on the extensibility and the convergence using superiority evaluation method, called rhombus –thinking, helps us get usable product programming ideas and provide rules for product innovation.

(2)Extension market

It explores the product’s extension market based on product divergence, product extensibility, product dependency, product implication and so on. It expands the market through the matter-element transformation of products and purchase ability and exploits distribution channel by matter-element transformations of marketing channel.

(3)Extension resource

It can transform enterprise uncontrollable internal and external resources into usable resources for enterprise by extension transformation and based on the idea of extension set.

(4)Innovation enterprise

It can collect the false and true parts, soft and hard parts harmoniously and reasonably, construct the positive and negative parts reasonable, decrease the positive and negative parts that are not propitious for company development, find the potential parts, and promote the potential parts that are propitious to company development, meanwhile prevent the negative parts.

(5)Extension marketing planning

Extension method should run through each component of marketing planning activities, implement the program reasonably, and create larger profit with less resource.

Therefore, with the rapid development of information technology, intensive competition of enterprises and a variety of customer needs, extension marketing provides an operationalization and new method for product innovation, market extension, and resource exploiting. The construction of extension marketing theory has significant theoretical and practical implication. However, we should notice that the extension marketing research is still at the beginning stage, and both the research contents and research scope need to be enriched and extended. The future research directions might include: service extension innovation, extension marketing based on the Internet, extension analysis of consumer behavior and so on. At the same time, we should emphasize the combination of extension marketing application and specific industry. Some scholars have already applied the extension marketing in real estate and tourism industry, and the application of extension marketing in the other industry will be inevitable in the future.