We report the experimental data of ammonia solubility in Athabasca bitumen measured at different temperatures and pressures ranging from 348 to 463 K and 1 to 4 MPa, respectively. The liquid-phase density of ammonia-saturated bitumen was measured for the samples that were taken during solubility measurements. The experimental data for ammonia solubility in bitumen were modeled using the Peng-Robinson equation of state. The volume-shift parameters of ammonia were tuned to represent the experimental density data of ammonia-saturated bitumen with an average absolute relative deviation percent (AARD%) of 0.218%. Also, tuning the binary interaction coefficient between ammonia and bitumen allowed the prediction of solubility data with an AARD of 8.537%. The data and the tuned model find applications in the reservoir modeling of solvent-aided thermal recovery of bitumen and heavy oil.