The invention provides a distributed-power-supply connection, measurement and control and protection all-in-one machine and method. The all-in-one machine includes a central controller which is used for controlling power generation quantity of a distributed power supply through use an anti-reflux control algorithm according to an energy parameter of a grid connection point so as to prevent redundant electricity of the distributed power supply from being returned to a power grid, also used for detecting happening of island according to the voltage and frequency parameters of the grid connection point and splitting the distributed power supply and the power grid in a regulated time after happening of the island, and also used for comparing electric energy quality data of a monitored grid connection point and a preset electric energy quality standard and controlling an electric energy quality unit to regulate an electric energy quality according to the comparison result so as to comply with the preset electric energy quality standard. The distributed-power-supply connection, measurement and control and protection all-in-one machine and method integrate and optimize island detection, anti-reflux control and electric energy quality control so as to form a control strategy of the all-in-one machine so that the control intelligent degree is improved and the construction cost of a system is reduced.