The magnetic characteristics of ethanol-water mixtures were investigated using our newly developed hybrid-type magnetometer based on a high-temperature superconducting quantum-interference device. The magnetization (M-H) curves of ethanol-water mixtures show good diamagnetic characteristics. The magnetic moments of the mixture show ethanol concentration dependence. However, the variation in magnetic moment differs from the characteristics expected by considering the magnetic moment ratio between water and ethanol, and volume-reduction rate. It showed two decrement regions separated at approximately 50-60% concentration values. It is also observed that the concentration dependence of the magnetic moment measured using the sample vibration method under a uniform magnetic field and that by the sample rotation method showed slightly different characteristics. These anomalies are attributed to the formation of clustered structures in the mixture. (C) 2017 Author(s). All article content, except where otherwise noted, is licensed under a Creative Commons Attribution (CC BY) license (http://creativecommons.org/licenses/by/4.0/).