Suicide is the issue which the modern society pays close attention to. This text probes into the morals topic of committing suicide from the view of Kant's moral philosophy, hoping to awake people to realize the essence of the life significance and avoid unnecessary suicide as well with its view that people should keep itself. Besides, Kant considers that people should not commit suicide by the reason that it not only violates God's intention, more importantly, it also violates natural law which requires the whole creation must keep itself. A rational being should not only regard human as a means, but also as an end. Suicide is making use of a person merely as a means; therefore a person is not regarded as an end and loses its human nature dignity, too. Furthermore, from other scholars' opinions with committing suicide, thinking of the morality, not all suicides are irrationally, there are still a few euthanasia types, forming the dignity of the human nature under the passive meaning.