Matlab*P is a flexible interactive system that enables computational scientists and engineers to use a high-level language to program cluster computers. The Matlab*P user writes code in the Matlab language. Parallelism is available via data-parallel operations on distributed objects and via task-parallel operations on multiple objects. Matlab*P can store distributed matrices in either full or sparse format. As in Matlab, most matrix operations apply equally to full or sparse operands. Here, we describe the design and implementation of Matlab*P’s sparse matrix support, and an application to a problem in computational fluid dynamics.