A number of professionals claim that moral bioenhancement (MB) is necessary for humanity to avert catastrophe. With the rapid advancements of science and technology, human beings have drastically altered their natural and social environments while their moral sensibility continues to be unaffected. They alleged that this is a mismatch, and since it becomes easier to harm than to benefit others, which they anticipate as a global threat, they promptly want MB to be obligatory to all. But the essay argues that MB is not necessary, and that it is not equivalent to moral enhancement (ME). In keeping with this argument, the essay advances the following: (1) a reexamination of ME and its relation to MB, (2) distinction between bioenhancement and biomedicine (BM), (3) the human being in relation to nature and technology, and (4) the meaning and axiology of MB.