The invention relates to a method for quickly detecting the water content of an emulsified asphalt cold-recycling mixture. The method comprises the following steps: (1) mixing an emulsified asphalt cold-recycling mixture sample according to the target mixture proportion design, or taking a sample from a production field; (2) weighting to obtain the mass of a beaker; (3) weighting to obtain the total mass of the beaker and a mixture; and (4) pouring out the emulsified asphalt cold-recycling mixture, weighting to obtain the total mass of the beaker, and emulsified asphalt, water, fine aggregates and the like adhered to the beaker, calculating a standard adherence rate P and an actual adherence rate P' of different external water blending quantities, and drawing a standard curve as an adjustment reference by taking the external water blending quantities as a horizontal ordinate and taking the adherence rates as a vertical coordinate. According to the method, test data is accurate and reliable, a test process is simple and quick, the water content can be monitored in real time during production of the emulsified asphalt cold-recycling mixture, the external water blending quantities are regulated, a wrapping effect of the emulsified asphalt and a compaction effect of the mixture are ensured, and an effective method is provided for production quality control over the emulsified asphalt cold-recycling mixture.