非洲大蜗牛（学名：Achatina fulica）是腹足纲动物，为陆栖蜗牛。俗名褐云玛瑙螺、菜螺、。

成体壳长一般为7-8公分，最大则可长到超过20公分。

壳略呈纺锤形，高约8厘米，质稍厚；螺层约六、七层，螺旋纹与生长纹相交错，体螺层大，螺旋纹不明显；壳面白或黄色，有红棕色条纹或焦褐色云状花纹；无厣，遇到干燥或冬眠时分泌乳白色粘液膜以封闭壳口。

Achatina fulica is a species of large land snail that belong in the Achatinidae family. It is also famously known as the giant African snail or giant African land snail. This snail species has been considered a significant cause in pest issues around the world. Internationally, it is the most frequently occurring type of snail invasive species.