As part of an ongoing project dealing with experimental and theoretical work on the solubility of weak electrolyte gases like ammonia, carbon dioxide, sulfur dioxide, hydrogen sulfide or hydrogen cyanide in aqueous phases, the simultaneous solubility of ammonia and carbon dioxide in water was measured in the temperature range from 313 K to 353 K at total pressures up to about 0.7 MPa. The model proposed by Edwards et al. (1978) is used to correlate the new as well as literature data (Goppert and Maurer (1988), Muller et al. (1988)). Experimental and calculated results are reported and compared.