Porous MOFs prepared from luminescent porphyrins as building blocks show extremely interesting oxygen sensing properties in gas phase. Compared to conventional oxygen-sensing materials it becomes possible to suppress aggregation of dye molecules and achieve high indicator content in the sensing material. High porosity and "free-standing" dye molecules are responsible for unprecedentedly efficient quenching of the luminescence by molecular oxygen. Significant quenching is observed already for the MOF based on a fluorescent porphyrin dye despite its short fluorescence decay time of several nanoseconds. Phosphorescence of MOFs that make use of analogous Pt(II) and Pd(II) porphyrins is quenched by trace amounts of oxygen. The bimolecular quenching constant kq is extremely high and exceeds by several folds the value obtained for the porphyrins immobilized in poly(trimethylsilylpropyne), a polymer with the highest oxygen permeability known. MOF growth on porous support materials paves the way for their practical applications in oxygen sensing in gas phase. Among several materials investigated, cross-linked poly(acrylonitrile) nanofibers were found to be particularly promising, since the oxygen-sensing characteristics are virtually the same as for the free crystals. The material shows fast and fully reversible response. A current limitation of the PCN-224 based MOFs in oxygen sensing is the crosstalk to humidity and the drastic decrease of the sensitivity at high humidity. Substitution of the dye molecules used as building blocks by fluorinated porphyrins may help to overcome the current limitation.