八格骨牌（Octomino），又称八连块，是一种多格骨牌，每块以八个全等的正方形连成，反射或旋转视作同一种共有三百六十九种。

An octomino (or 8-omino) is a polyomino of order 8, that is, a polygon in the plane made of 8 equal-sized squares connected edge-to-edge. The name of this type of figure is formed with the prefix oct(a)-. When rotations and reflections are not considered to be distinct shapes, there are 369 different free octominoes. When reflections are considered distinct, there are 704 one-sided octominoes. When rotations are also considered distinct, there are 2,725 fixed octominoes.