E-Commerce systems have become ubiquitous. However, it is a challenge to create high quality e-commerce systems respecting time and budgetary constraints. In this paper, we present a life-cycle testing process for e-commerce systems by adapting OO-TTCN-3, an object-oriented extension of a formal test language TTCN-3, to enable the efficient specification of tests in object-oriented, e-commerce development environments. This extension is meant to ease life-cycle testing, facilitate test case reuse between different test phases, and provide a unified Abstract Test Suite (ATS) interface to test tools. A case study shows how to apply the approach to a typical e-commerce system based on a high-yield, risk-directed strategy.