Abstract: The point estimation of parameter of Poisson distribution for truncated and censored data is studied by EM algorithm and MCMC method. The missing data is filled in and the complete data is obtained. The EM iterative formula of the parameter is given. After sampling from the full conditional distributions, Gibbs samples of the parameter are obtained, the mean of Gibbs samples is taken as MCMC estimation of the parameter. The random simulation results show that the effect of the estimation is good, and the estimation is relatively stable and precision is also higher.