体型は、背鰭の欠如という点も含めランチュウとよく似ています。しかし、頭の肉瘤はなく、口は尖った形をしています。胴部もランチュウに比べて細長く、後方になるに従い太くなります。

The Nankin goldfish’s body shape is very similar to that of the Ranchu, including the lack of dorsal fins. However, it has no head growth and its mouth is pointed. The body is also elongated compared to the Ranchu, becoming thicker toward the rear.