To provide a business execution model optimization device allowing efficient execution of business.

This business execution model optimization device 10 includes: a model storage means 20 storing a business execution model including information related to each of a plurality of pieces of work; an execution history database 30 storing the information related to each of the plurality of pieces of the work in the business executed along the business execution model associatively to the executed business; a difference detection means 40 detecting difference between the information related to each of the plurality of pieces of the work stored in the execution history database 30 and the information related to each of the plurality of pieces of the work in the business execution model stored in the model storage means 20; a difference digitalization means 50 quantifying the difference detected by the difference detection means 40 about each of the plurality of pieces of the work; and an amendment bill presentation means 60 presenting the work presenting the difference when the difference quantified by the difference digitalization means exceeds a predetermined target value.