The invention provides a culture method of Aspergillus niger for producing citric acid. The method comprises the following steps: inoculating Aspergillus niger in an Aspergillus niger culture solution for culture, wherein the respiratory quotient of the Aspergillus niger thallus is 0.7-1.5 under the conditions of culture; and maintaining for 2-8 hours at the respiratory quotient. According to themethod provided by the invention, whether the growth state of the Aspergillus niger is applicable to subsequent fermentation is judged according to the numerical value of the respiratory quotient, and culture is maintained for 2-8 hours at the state that the respiratory quotient is 0.7-1.5, so that the obtained Aspergillus niger has high fermentation efficiency in the subsequent fermentation process; and the method provided by the invention is slightly influenced by personal factors, thereby maintaining the stability of Aspergillus niger culture among batches.