NOVELTY - An apparatus and a method for livestock wastewater treatment are provided to effectively treat livestock wastewater in treatment facility of a small area by reducing contamination load of livestock wastewater, and effectively perform nitrification and denitrification by maintaining a certain level of pH during the treatment process.    DETAILED DESCRIPTION - A method for livestock wastewater treatment comprises the steps of diving a flow equalization tank into a high concentrated livestock wastewater flow equalization tank and a low concentrated livestock wastewater flow equalization tank and equalizing quality of wastewater of respective livestock wastewater flow equalization tanks; solid-liquid separating high concentrated wastewater from the equalized wastewater so that the separated high concentrated wastewater is injected and mixed in the low concentrated livestock wastewater flow equalization tank, and solid-liquid separating the mixed low concentrated livestock wastewater again to reduce organic load; injecting the organic load reduced livestock wastewater into a C/N ratio equalization tank, thereby adjusting the C/N ratio equalization tank to obtain a C/N ratio suitable for denitrification; injecting the livestock wastewater of the C/N ratio equalization tank to a first microorganism reaction tank, dividing operation of the first microorganism reaction tank for one day into anaerobic and aerobic operations, and removing organic matter and nitrogen in the livestock wastewater through organic matter decomposition, nitrification and denitrification as maintaining a pH changing during the treatment process in the proper range; neutralizing and coagulating the wastewater to solid-liquid separate the livestock wastewater treated in the first microorganism reaction tank and properly remove color and phosphorus from the livestock wastewater; and purifying the livestock wastewater and removing color and phosphorus therefrom by solid-liquid separating the livestock wastewater, returning some of sludge to the first microorganism reaction tank, and transferring the separated treated water to a treated water storage tank.