The oxygen-tolerant, NAD+-reducing soluble hydrogenase (SH) from Ralstonia eutropha H16 is a promising catalyst for cofactor regeneration in enzyme-catalysed reduction processes. The technical use of the isolated enzyme, however, is limited by its relatively low stability under operational conditions such as agitation, elevated temperature or addition of co-solvents. The maximum half-life at a reaction temperature of 35 ◦C and pH 8.0 was only 5.3 h. In order to enhance the stability of the enzyme, it was immobilised onto the anionic resin AmberliteTM FPA54. At an immobilisation yield of 93.4% for adsorptive and 100% for covalent attachment, corresponding activities of 48.9 and 39.3%, respectively, were obtained. Covalent binding always yielded superior stabilisation. At elevated temperature and under agitation, stabilisation was further increased by modification of the covalently bound SH with methoxy-poly(ethylene) glycol (mPEG). A comparable effect was not achieved when SH modification was performed before immobilisation. In stationary aqueous solution, half-lives of up to 161 h at 25 ◦C and 32 h at 35 ◦C were obtained. In presence of the technically relevant co-solvents DMSO, DMF, 2-propanol and [EMIM][EtSO4] half-lives of 14–29 h can now be achieved.