The invention discloses a soft measurement method for the key parameters in the edible fungus fermentation production process, and the method is used for solving the problem of online estimation of the key biochemical quantity which is difficult to measure in real time in the edible fungus fermentation process. The method comprises the following steps: firstly, by analyzing the process mechanism of an edible fungus fermentation process, selecting a proper auxiliary variable and establishing a training sample database according to the historical tank batch data; constructing a least squares support vector machine soft measurement training sample database by combining the main variables and the auxiliary variables of the current to-be-predicted tank batch fermentation process with the main variables and the historical auxiliary variables of the historical fermentation process, and constructing a soft measurement model corresponding to the soft measurement training sample database, and then optimizing the normalization parameter gamma and the kernel parameter sigma 2 in the soft measurement model by means of a grey wolf algorithm, and establishing a least squares support vector machine soft measurement model based on the grey-wolf optimization, and finally obtaining a corresponding key biochemical parameter prediction value. According to the method, the grey-wolf optimization algorithm for simulating the grey wolf behaviors is adopted, the structure is simple, the parameter setting is small, the global searching capability is high, and the gradient information is not considered.