An Internet advertisement method and system that issues an authentication key for enabling selected target customers to receive a commercial sample at a membership-based offline store by performing an advertisement in the form of a banner on a web page of an online market, such as an Internet shopping mall, such that an advertiser can conveniently satisfy needs of customers desiring to purchase goods after receiving the sample without delivering the sample, a targeting goods advertisement can be effectively performed, membership-based offline stores can be publicized, and increasing visits from customers can lead to an increase in sales. The Internet advertisement method includes providing an advertisement including information on providing a sample, and generating an authentication key for enabling a customer terminal selecting the advertisement and requesting a sample of advertised goods to receive the sample at an offline store.