Indonesia is one of the most populous countries in Southeast Asia, and is the third-largest mobile commerce market in the world, behind China and India. The country also has high mobile penetration rate and fast-growing technologies, allowing its citizens to connect to the Internet easily. This makes the e-Commerce market in Indonesia one of the most attractive in emerging countries. As one of the leading technology startups in Indonesia, GO-JEK continuously seeks new opportunities to reach into a wider market. The latest feature launched by the company is GO-DEALS, which is a mobile marketplace for online discount vouchers. GO-DEALS plans to penetrate into teenage market in Jakarta, by first identifying and analyzing the online purchase behavior and purchase intention of the teenage target market. This study requires several theories of online purchase behavior, purchase intention, e-trust, and e-loyalty. Data are collected from high-school and university students aged 15-22 years old who reside at Jakarta. Online questionnaires are distributed to at least 30 respondents fitting this demography. From the study results, the authors can conclude that the online purchase behavior and purchase intention of GO-DEALS teenage consumers do affect the e-trust and e-loyalty of GO-DEALS. The online purchase behavior of GO-DEALS teenage consumers shows that they like to shop online because it is convenient and may save their money, and tend to look for promotions when shopping online from platforms they trust. The purchase intention of GO-DEALS teenage consumers shows that they would purchase online discount vouchers from GO-DEALS because of the interesting promotions, variety, quality, availability, and ease-ofuse of the products