In this paper the effect of the surface functionalization of the carbon nanotubes (CNT) networked films with a metalloporphyrins layer is investigated for gas sensing. Modified film exhibits an increased sensitivity of the electrical resistance towards the concentrations of common volatile compounds (alcohols, amines, aromatic and ketones), at room temperature. Furthermore, a part of the adsorption properties of the functional units is transferred to the sensor signal and, as a consequence, the selectivity of the sensor is also modified. Principal Component Analysis (PCA) demonstrates that the functionalization provides enough selectivity change to turn a triplicate of the same CNT film into an effective sensor array capable of the compounds recognition.These findings are then promising for the development of arrays of CNT-based gas nanosensors with broad selectivities for fingerprinting analysis of complex samples.