Kantian ethics is a moral theory based on the fundamental spirit of Kant and critical reading of his text. This thesis at first shows the meaning of the concept of Kantian ethics and the necessity and the probable contribution of applicatory problems such as suicide for the construction of a moral theory through a critic of Allen Wood. Secondly, this thesis has discusses three interpretations of categorical imperative described by Christine Korsgaard and takes them as the basis of the evaluation of suicide. Then, this thesis tries to define suicide and tests the Kant’s arguments against suicide, then provides its own version of evaluation of suicide. In the end, this article shows the modification to Kant proposed by contemporary scholars and points out the reasons why they may not be proper modification of Kant’s theory.