蔚蓝色（英语：Cerulean）是一个蓝色系的颜色，近似于天空的颜色。其英文「cerulean」一词系来自拉丁语词汇「caeruleum」（意思为天空、天堂）。

Cerulean (/səˈruːliən/), also spelled caerulean, is a color term that may be applied to certain colors with the hue ranging roughly between blue and cyan, overlapping with both. It also largely overlaps with azure and sky blue, although cerulean is dimmer.