Abstract: Sodium thiocyanate is one of the prohibited additives in raw milk. The excess intake of sodium thiocyanate is harmful for human health and always results in acute toxicity and systemic disease characterized by dysfunction of digestive system and nervous system as well as skin damage. Low intake of sodium thiocyanate is able to interfere with the absorption and utilization of iodine and may subsequently cause thyroid diseases. The content, source, toxic effects and its underling mechanism of sodium thiocyanate in raw milk are reviewed, in hoping to provide references for the effective control of sodium thiocyanate content in raw milk.