Percolation threshold of free percolation 3-D model is calculated by renormalization group method.On the basis of this, a 3-D model of self-similar percolation is developed.

• 采用重正化群方法算出三维自由渗流模型的渗流阀值，在此基础上提出三维具有自相似性质的渗流模型。