This paper deals with the theoretical derivation of the modified Haldane model of the substrate inhibition in the microbial growth processes. Based on the biological concepts of substrate-receptor working mechanisms, a new multiplex microbial substrate inhibition mechanism has been considered, which is natural expansion of the single substrate inhibition in the enzyme reaction. Finally, modified Haldane model of the microbial substrate inhibition turned out to be well designed with a biological meaningful constant of total substrate inhibition concentration.