成年是很多青少年引頸期盼到來的一天，但究竟是18 歲或20歲算成年則眾說紛紜。這其實是因為過去我國民法及刑法規定並不一致所導致。
我國开法第18 條規定，18歲以下的青少年觸犯刑法可以減輕其刑，此乃考量青少年可能會因為情緒管理尚未成熟，可能會因為衝動而犯罪。但，隨著年齡增長，應該要漸漸能夠控制自身的行為。因此刑法以18歲為為自己的行為負完全責任的門檻。
另外一方面，民法則是考慮青少年初出社會，可能無法周詳地考慮各種交易行為可能為自己生活造成的負擔，因此設定18歲為成年門檻（民法第12條），過
18歲以後便要為自己的行為負完全責任。
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Turning 18 or 20 is often a milestone that many teenagers look forward to, but there's been confusion about which age legally counts as adulthood in Taiwan. This confusion stems from the fact that, in the past, Taiwan's Civil Code and Criminal Code had different definitions of the legal age of adulthood.
According to Article 18 of Taiwan's Criminal Code, if a person under the age of 18 commits a crime, the punishment may be reduced. This is based on the understanding that young people may not yet have fully developed emotional control and may act impulsively. However, as a person grows older, they are expected to take more responsibility for their actions. That's why the Criminal Code sets 18 as the age at which a person must take full legal responsibility for their actions.
On the other hand, the Civil Code takes into account that young people who are just entering society may not fully understand the consequences of various financial or legal transactions. Therefore, Article 12 of the Civil Code sets the age of majority at 18. After turning 18, a person is legally responsible for all their actions.
June 1, 2025