One of the rare but more prominent cases of judicial protection of the existing constitution is the revision of constitutional amendments. From among courts that review amendments, this study presents India’s Supreme Court’s practice, which is regarded as a model. India’s constitution does not contain any unamendable provisions or explicit authorization for judicial control over constitutional amendments, yet the court reviews constitutional amendments on grounds of protecting the constitution’s basic structure. India’s Supreme Court’s practice is a typical example of a court imposing an implicit limitation upon constitutional amendments. Therefore, before analyzing the basic structure doctrine, the study briefly examines the nature of the implicit limitations of constitutional amendments and some issues that may arise in their justification.