In this paper, according to the characteristics of parametric landscape design, practical landscape architecture is selected for parameter and rule sets, and then the program calculation is established by parametric software to realize the digital design of urban landscapes. The parametric model of urban architectural design is designed for site factor indexing, construction, and management of space and form. The automatic identification model based on the building plan for the construction of building functions is carried out to generate candidate target areas and location refinement analysis, and the parametric generation of the urban landscape is optimized for design. Compared to the initial scheme, the economic and technical indicators increased the volume ratio by 11.2%, the building density by 17.3%, and the green area ratio by 3.6%. The three performance indicators 1/VG̅, CHIS̅ and 1/VB̅ of Rop are 8.5%, 35.6% and 20.8%, respectively.