In the software development investment planning stage and bidding stage, the requirement specification or the list of function points have not yet been formed, so the specific development realization of the system and the development workload information of the project cannot be clarified. By establishing the workload quota based on the function module, the system structure and workload estimation can be quickly judged without detailed demand analysis. The investment estimation time is greatly saved. For the individual requirements that the workload quota of functional modules cannot cover, the workload quota based on the requirement description is formed by establishing the database of the corresponding relationship between the historical requirement description and the workload measurement results, and the short text similarity matching algorithm based on the bag of words model is used to search. The two kinds of workload quotas jointly support the rapid estimation of software development workload.