The invention relates to a metronidazole production method which comprises the steps of performing a hydroxylation reaction, adding a hydroxylation reaction product into methanol, obtaining methyl formate through recovering, further treating methyl formate to form a formamide product, neutralizing the other part of the hydroxylation reaction product to form a metronidazole product and a neutralized mother solution, adding sulfuric acid into the neutralized mother solution, performing crystallization treatment to form sodium sulfate, sodium formate and crystal residue, adding the crystal residue into a glycol recovery kettle for reaction to generate waste residue, and performing incineration treatment on the waste residue. According to the metronidazole production method, ammonia gas is added into methyl formate generated in a metronidazole production process for reaction to generate formamide for formic acid recovery; most formic acid is recovered; and the formamide product is generated. At the same time, the neutralized mother solution after the metronidazole product is obtained is treated and separated to form sodium sulfate and sodium formate; the production method is high in comprehensive efficiency; in addition, the discharge of waste is low; and the method has small environmental influence.