Seeking for advanced gas sensing materials with high responses to trace acetone gases is of great importance for the diagnosis of diabetes. However, it is still challenging to exhibit a reliable response for gas sensing devices in high humidity environment. Herein, zinc ferrite (ZnxFe3-xO4) sensing materials with different zinc contents of x varying from 0 to 0.6 were synthesized by a facile solvothermal route. The acetone sensing properties of ZnxFe3-xO4-sensors showed a highly sensitive dependence with Zn/Fe ratio variations. As a result, the Zn0.4Fe2.6O4 spheres based sensors displayed the highest response (Ra/Rg = 157) towards 100 ppm acetone and excellent selectivity compared to the other zinc ferrite samples. The sensor also showed obvious signal to trace acetone in the simulated breath of diabetic patients. Controlling zinc content in ferrites provides an alternative new strategy to realize effective acetone detection and facilitate human exhaled breath analysis.