Aki (秋) is Japanese for "autumn".
It otherwise may refer to:
- Shizuha Aki (秋 静葉), the older one of the Aki sisters
- Minoriko Aki (秋 穣子), the younger one of the Aki sisters
- Aki★Eda (秋★枝), pen-name for the artist who drew for various official Touhou works, part of circle Rocket Fuel 21 (ロケット燃料★21)
- aki no sora (秋の空), a doujin arrange circle