In electric circuits, errors are ineluctable. When upper bits of binary signals flip due to noise, the value will increase or decrease drastically. On the other hand, if stochastic numbers are used, the change on their values are the same since all the bits have the same weight. Therefore, stochastic computing, a computation method based on stochastic numbers, is attracting interest. Stochastic computing does have error tolerance, but cannot restore the bit stream if the bits are erroneous. Here, this paper focuses on evaluating the error-free value from the bit error rate and the erroneous value. In this paper, we propose a method to correct errors of stochastic numbers by measuring the bit error rate and filtering the values properly. From experimental evaluations, in environment with errors of more than 21%, this proposal will give a better peak-signal-to-noise ratio compared with a conventional error correction coding.