A function model was used to quantify the vulnerability of the Haihe River basin on the basis of sensitivity, adaptability of the water resources system, exposure and drought disaster risk. Surface water resources vulnerability was assessed for a benchmark year (2000) using the function and indicator models and for modelled future climate scenarios using only the function assessment model. In the results, surface water resources vulnerability was greater when exposure, disaster risk and water quality factors were considered. Both models gave the result that vulnerability of water resources in study area was high; all the regions were rated ‘highly’, ‘strongly’, or ‘extremely’ fragile.