The invention relates to a treatment method for small water quantity refractory wastewater deep purifying and utilizing. The method comprises the following steps: step one, pre-filtrating wastewater is performed firstly; step two, the pH value of the wastewater is adjusted to 3-5 to ensure the wastewater to present subacidity; step three, the wastewater flows into a spout-fluid bed reaction tower, the wastewater is processed through a micro-electrolysis method, and micro-electrolysis composite functional material is utilized in the micro-electrolysis method; step four, the wastewater is processed through a photo-assisted fenton catalytic oxidation method; step five, the pH value of the wastewater is adjusted to 6.8-7.8, and then the wastewater is processed through strengthen flocculation method; step six, the wastewater flows to a microwave catalysis reactor, and is processed through a microwave catalytic oxidation method; step seven, the wastewater flows into a UV photochemical reactor, and is processed through the UV photocatalysis; step eight, the wastewater flows into a gravitation filter, and the wastewater can be clarified to meet the requirement of the reuse water quality. The invention also provides equipment for performing the treatment method.