Abstract A multiple-porosity petrophysical model that honours heterogeneity and the complex geologic characterization of a giant gas reservoir in Bolivia has been developed. The model handles five different porosity types: macrofracture, low conductivity fracture, microfracture, shale, and dispersed and intergranular porosity. Geological evaluation indicates that these porosities have some degree of connectivity. Due to the various porosity components, the model permits a more accurate estimation of the cementation exponent (m) and provides a better understanding of the gas storage and water saturation distribution in the reservoir. The model also has the capability to account for lithological variations throughout the field. There is a wide variety of available models for estimating petrophysical properties, but none was found that could represent the available data for this field realistically. The Borai correlation, developed exclusively with data from Abu Dhabi carbonate reservoirs, has been used in the past to evaluate the Bolivian reservoir. As a consequence, we undertook the petrophysical analysis from a different perspective and developed the proposed model. Taking into account the various porosity types, lithology and structures depicted in the field geological characterization has been essential to develop the solid petrophysical model presented in this study. This in turn is an important aid for understanding reservoir behaviour. The proposed multiple-porosity model allows sound characterization of the Bolivian gas reservoir considered in this study because it is strongly linked to the field geological heterogeneity. We anticipate that given the flexibility of the model, it will be applicable for characterization of sandstone reservoirs with similar characteristics in other regions around the world.