Abstract: This article discusses the difference between two Bayesian models. With model 1, it is assumed that x_i（i=1,2）is conditional independent under θ_i（i=1,2）. While with model 2, it is assumed that x_i（i=1,2）is unconditional independent. The question is that when working for the Bayesian estimation of θ₁, is there any difference on the results under the two different models? The numerical comparison shows that there is only small difference between the results. So the simpler model 2 can replace the model 1, when Bayesian estimation of θ₁ is calculated.

Key words: conditional independent, unconditional independent, Bayesian estimation, Bayesian model, conditional independent, unconditional independent, Bayesian estimation