Abstract: Compression of geometry instruction stream in distributed parallel rendering systems can alleviate network bandwidth bottleneck. LZW method is used in op-codes compression. A sphere symmetric-grid method is used for normal compression. Prediction delta coding with DPCM model is used in position and color compression. 4 kinds of predictions and adaptive quantization are used in position compression. Multiple approaches work well in geometry instruction stream compression. The average length of instructions is compressed to 1/3 of the original one with almost no loss of quality and the executing speed is better than 400 instructions/ms.