To improve the extraction yield of succinic acid which produced by microbial fermentation, trioctylamine /octanol was used as extraction agent to extract succinate form fermentation broth. The pre-treatment of fermentation broth as well as preparation of succinic acid ammonium using ammonia to re-extraction were investigated. Results showed that the rate of succinic acid extraction from fermentation broth pre-treated by cation exchange resin reached 91.3%, which was higher than that of by sulfuric acid. Aammonia was an excellence re-extraction agent and the extractant (trioctylamine /octano) could be reusable. When extractant was recycled five times, both average rates of extraction and re-extraction were 90.4% and 94.8%, respectively, indicating no obvious changes.