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Voltage imaging provides a direct measure of neuronal activity and holds significant promise for understanding information processing within individual neurons and across populations. However, imaging voltage over large neuronal populations has been challenging due to the simultaneous requirements of high imaging speed and signal-to-noise ratio, large volume coverage and low photobleaching rate. To overcome this challenge, we developed a confocal light field microscope that surpassed the traditional limits in speed and noise performance by incorporating speed-enhanced camera, fast and robust scanning mechanism, laser-speckle-noise elimination and optimized light efficiency, enabling long-term volumetric voltage imaging. With this method, we achieved simultaneous recording from more than 300 spiking neurons within an 800 µm diameter and 180 µm thick volume in the mouse cortex, for more than 20 minutes. By integrating the spatial and voltage activity profiles, we have mapped three-dimensional neural coordination patterns in awake mouse brain. Our advancements present a robust method for routine application in volumetric voltage imaging.