The invention discloses an efficient and deep treatment process for high-concentration waste water in a natural gas industry. High-concentration industrial wastewater is subjected to physicochemical pretreatment to improve the biodegradability of the wastewater, and toxic and harmful substances in the wastewater are eliminated simultaneously, medium and low-concentration gas-field wastewater and domestic wastewater are mixed, and biochemical treatment is performed, accordingly, the biochemical treatment efficiency is improved, poison and impact resistances of a system are enhanced, and the denitrification function is strengthened. The technological process is simple, the operation is stable, the removal rate is high, investments and operation costs are saved, the process can be fully applied to treat industrial wastewater of various gas fields, and discharged water can achieve environment friendly emission standards required by the country.