The utility model discloses a milk foam generator of a coffee maker, comprising a milk tank, wherein the top part of the milk tank is provided with a support, a foam generator body is placed on the support, the foam generator body is respectively connected to an inlet milk pipe, a steam pipe and a milk foam sprayer, the foam generator body is internally provided with a first emulsification chamber, the first emulsification chamber is communicated with an air inlet channel, and the air inlet channel is internally provided with an air inlet adjustment member. The utility model has a simple structure, and is convenient for adjusting the emulsification effect of the milk foams.