A method for treating substrates with treating liquids, using a treating tank for storing the treating liquids, a holding mechanism for holding the substrates and placing the substrates in a treating position inside the treating tank, a first and a second treating liquid supply device, a temperature control device, and a control device. A first treating liquid is supplied into the treating tank, then a second treating liquid of lower surface tension and higher boiling point than the first treating liquid, is supplied into the treating tank, and placed in a temperature range above the boiling point of the first treating liquid and below the boiling point of the second treating liquid, and then controlling the second treating liquid supply device to replace the first treating liquid stored in the treating tank with the second treating liquid, and controlling the temperature control device to maintain the second treating liquid in the same said temperature range.