The study was conducted to develop a rumen protected γ-aminobutyric acid (GABA) with low ruminal degradability and high post-ruminal dissolution. GABA content, coating material and pressure were used as variables in a L9(34) orthogonal design to select samples with high insoluble rate, then ruminal degradability and post-ruminal dissolution were determined. The results showed as follows: as coating material, solid palm oil product was superior to the mixture of solid palm oil and glyceryl monostearate. The sample produced under the condition of 50% GABA, encapsulated with solid palm oil and under the pressure of 11 kPa was degraded at least in rumen. Its utilization efficiency was 75.8%. The sample produced under the conditions of GABA content of 50%, encapsulated with solid palm oil and glyceryl monostearate equal mass mixture and under the pressure of pressure 9 kPa presented the highest post-ruminal dissolution rate. It is suggested that the solid palm oil can be used as coating material to produced rumen protected GABA with low ruminal degradability and high post-ruminal dissolution.［Chinese Journal of Animal Nutrition, 2010，22（5）:1451-1456］