When a market has more variety and substitutes for a product, customers have the option to choose the best among alternatives. Majority of companies are trying to pull customers towards them and they use all possible methods. Among them, advertising is the main tool used by almost all companies. This paper aims study on the influence of advertising on consumer brand preference and loyalty for hair shampoo in Madurai. This study is based on a survey of 356 customers in Madurai town. The results show that different age segments and sex of the respondents are not influenced by advertising at the time of purchase of shampoo. Among shampoo brands, Sun Silk, Clinic Plus and Dove are the most preferred brands in Madurai. The advantage of advertising is highlighted in the present study. Advertising serves as a key tool for creating product awareness and help potential users to take a final decision to purchase. Celebrity and promotional offer in the advertisement are the influencing factor of the respondents. Keywords: Advertisement, Brand Preference, Brand loyalty, consumer loyalty.