Given the security issues caused by electrostatic discharge in electron devices, triboelectrification has attracted extensive attention as a new energy-generation and -collection method. However, high output impedance and low current density will hinder its further development and limit many practical applications. Here, we report an effective method to circumvent these limitations by introducing a vacuum environment into relative movements. By combining discharge, the tribocurrent has two or three orders of magnitude enhancement during different triboelectrification processes. In traditional devices, the vacuum sliding triboelectric nanogenerator (VS-TENG) exhibits an ultrahigh average power of 173.8 W m−2·Hz−1 and sets a record of the triboelectrification driven by rotate mode. By shrinking the vacuum environment into a vacuum silicon tube, the current density of conventional TENGs can span from the microamp to the milliamp level. This work develops a universal strategy to enhance the output performance in energy harvesting.