Even entering Internet Era, the crimes of fraud are not only exiting but also do well in internet-trading. They are therefore connection with the protection of consumer. In this article, the author analyzes the role of criminal law and protection of consumer in the beginning. There is no criminal code in the Protection of Consumer Act in Taiwan so far. But only some complementary codes accompany the protection of Food, drug and fair trade with. Relatively, the penal codes play more important role to protecting consumers in Japan than in Taiwan. That would be a reference. Secondly, the author illustrates the crimes of Fraud on internet. There are two types of frauds, including internet trade and internet payment. The methods of fraud are told separately. Finally, the suggestions.