Abstract The microglial extracellular traps(MiETs) were appeared in glioblastoma multiforme (GBM), but the underlying molecular mechanisms and functions were unknown. In this study, we aimed to explore the ability of GBM-derived UL16-binding protein 2 (ULBP2) on activating MiETs and manipulating microglia to support GBM development. Herein, ULBP2 was identified as a key upregulated protein in GBM and triggered MiETs formation. In turn, MiETs accelerated GBM malignant growth.