透写纸（Tracing paper）又称描图纸，是一种半透明纸。它是将未裁剪和装订的纸张浸入优质硫酸几秒时间制成的。这种酸将部分纤维素转成淀粉质而具有凝胶状和不可渗透的特性。当这种处理过的纸张被彻底清洗和干燥过后，得到的产品比原来的纸张要抗张耐用得多。透写纸耐油脂并且很大程度上水、气密。

透写纸名字源于艺术家能够映描图像于其上。当透写纸被置放于一副图画之上时，很容易可以透过透写纸看到图画。因此，艺术家能够很方便的发现图画的边际线并映描到透写纸上。

另有一种缝纫用透写纸，上面为有颜色的蜡质，放于纸样和布料之间，用齿轮透写纸样上的指示线条，蜡质线用水清洗即可去掉。

Tracing paper is paper made to have low opacity, allowing light to pass through. It was originally developed for architects and design engineers to create drawings which could be copied precisely using the diazo copy process, it then found many other uses. The original use for drawing and tracing was largely superseded by technologies which do not require diazo copying or manual copying (by tracing) of drawings.