Stability of Q-BPM is very important in ATF2. Frequency shift of Q-BPM due to room temperature variation was measured to be -0.14MHz/degree. We also tested using the Q-BPM attached on a Q-magnet in the beam line. Turning on the magnet increased the temperature of the BPM ~ 3 degree and shifted the frequency ~0.3MHz. It also affected on X-Y isolation of the BPM a little.