This article addresses the optimal design of a geothermal binary trigeneration system for simultaneous cooling, heating, and power generation. A new processing network with alternative processing pathways is proposed. The major processing sections include geofluid production, Organic Rankine Cycle (ORC) evaporation, power generation, heat redistribution, cooling generation, condensing, and geofluid injection. Based on the superstructure, a cradle-to-gate life cycle analysis and techno-economic analysis are integrated with multiobjective optimization to simultaneously optimize the life cycle environmental impacts and the economic performance. To this end, a mixed integer nonlinear programming (MINLP) model is proposed to select the optimal processing pathway in terms of both greenhouse gas emissions and total annualized cost. A case study is also presented to cope with the seasonal demand of cooling, heating, and power to illustrate the application of the proposed modelling and solution methods.