The compressor is a device that served to increase the pressure and temperature of the air before entering the combustion chamber. The compressor consisted of several stages and at each level the air pressure is increased. Gas turbine that used in PLTGU Priok Block 3 is gas turbine mitsubishi type M701F. In this type, the compressor consisted of 17 stages that equipped with 3 bleed valve to prevent surging during acceleration and deceleration. Surging is a phenomenon that occurs in the compressor (especially the axial compressor) when the flow of air flowing into the compressor, the air flow will drop dramatically and can not be maintained again because of increased pressure discharge compressor exceeds the pressure on the compressor, so there will be backflow ) on the compressor. The problem that occurred in PLTGU Priok Block 3 is expansion joint LP bleed valve GT 3.2 has broken. The damage caused an increase in temperature in the fuel gas system-gas turbine building to exceed the allowable temperature standard of 80 oC which in the long term potentially damages the instrumentation and control equipment installed in the fuel gas system-gas turbine building. This study aimed to analyze the resistance of modified expansion joint LP bleed valve GT 3.2 in receiving the maximum temperature and pressure through the LP bleed line. The method used in this study is the calculation of pipe tension and thermal expansion that occur in the modified expansion joint pipe. The design of modified expansion joint LP bleed valve GT 3.2 is also made in the form of simulation using Computational Fluid Dynamics (CFD) method with ANSYS 16 software. Based on the calculations proved that the modification of expansion joint LP bleed valve is flexible enough to absorb the expansion due to temperature changes. The CFD simulation showed that modified expansion joint LP bleed valve is good enough to drain the LP bleed air, but the small open gap caused the backflow to the outlet. The backflow had characteristics that are very small, low speed and 1 bar pressure.