Based on considering the differences of different income residents on housing, we divide the residents into two types;combine the characteristic of resident housing preference. Through theoretical derivation we conclude that the income gap has threshold effect on real estate price bubble. Then, we construct the panel smoothing transformation model, the empirical conclusion is the same with the theoretical analysis: the effect of income gap on the house price bubble exists the threshold effect. If the income gap is lower than the threshold value, the influence is inhibition effect, or else is t...