各國對於未成年人的同意性行為，均於一定年齡範圍內利用刑法加以規範，此係考量未成年人欠缺完全的同意能力，或者基於保護未成年人的健全發展之需要。近時國內學說主張對於幼年者性交猥褻罪應該除罪化。對此問題，本文利用日本立法、學說與實務見解與其他國家立法加以比較，試以探索未來可能的修法方向。

In the regard of the unsound consent ability and the mental and physical development of minors, many countries limit minors' ability to consent sexual intercourse by criminal law. In Taiwan, academia recently suggest to revise the Criminal law's Article 227 Paragraph 3 and Paragraph 4 to decriminalize consensual sexual intercourse involving minors. In this regard, the essay compares Japan with other countries on law, academic comments and judicial opinions of consensual sexual intercourse involving minors. The study could be an important reference for improving related policy.