Phase-field method has recently been extensively employed to model mesoscale domain morphology and property evolution of functional materials for potential applications to nano-electromechanical systems, non-volatile memories, and energy conversion and storage. In this talk, we will present our recent effort in establishing a user-friendly computational environment that allows one to efficiently carry out phase-field simulations to model, analyze and predict domain/microstructure evolution under mechanical, electric, magnetic and chemical stimuli. It consists of a thermodynamic database for functional materials, a digital domain structure/microstructure builder, a set of domain/microstructure and local-field evolvers, a microstructure repository, and a multifunctional property predictor. Its applications will be demonstrated using specific examples from ferroelectrics, ferromagnetics, and solid electrolytes. This phase-field simulation environment will make it possible to perform phase-field simulations in a high-throughput manner to generate domain/microstructure/phase diagrams and massive microstructure-property data, which can be employed to guide experimental growth and design of functional materials.