Hollow fiber membrane modules have been employed for heat and moisture recovery from ventilation air. There are several benefits with this structure. The contact area is large. The resulting NTU (Number of Transfer Units) is high, which implicates a high performance. In this research, the governing equations for heat and moisture transfer in the module are proposed. The equations are then normalized with dimensionless parameters. Following this step, an analytical solution is obtained for the dimensionless differential governing equations. With the developed analytical solution, the sensible and latent heat exchange effectiveness could be estimated by simple algebraic calculations. This provides a convenient yet accurate tool for component design and system optimization. Experiments are conducted to validate the model. Effects of varying operating conditions on module performances are discussed. The study provides a tool for hollow fiber module optimization with simple correlations. (C) 2010 Elsevier B.V. All rights reserved.