Abstract Process simulation has become an accepted tool for the performance, design, and optimization calculations of solar desalination process units. Solving the mathematical models representing these units and systems is a tedious and repetitive problem. Nested iterative procedures are usually needed to solve these models. Also, the process configurations are characterized by existence of a number of recycle streams. To tackle these problems, several researchers have developed different methods, techniques, and computer programs for the simulation of a very wide range of variety of solar desalination process units and systems. It is of interest in this work to show and demonstrate a new program working under Matlab/SimuLink environments for solar desalination processes calculation and modeling. Using these environments a visual design and simulation for different types and configurations of standalone (common) and solar desalination processes can be performed. Embedded user block programming with SimuLink is implemented to construct a flexible reliable and friendly user-interface package. The solar heating systems and desalination plant components (named here as blocks), such as heat exchangers, flash chambers, evaporators, pumps, steam ejector, compressor, reverse osmosis membrane, pipes, etc., are stored as icons in a visual library. This library enables the user to construct different configurations by just clicking the mouse over the required units (blocks). The interface aids designers, and operators to perform different analyses and calculations such as energy, exergy, and thermoeconomics. Typical desalination processes such as multi stage flash, and reverse osmosis are presented to show the wide scope and the validity, reliability, and capability of the developed package.