Friction is the central cause for about 1/3 of the primary energy dissipation, severely impacting the performance limits of micro and nanoscale mechanical devices. Especially in two-dimensional semiconductor devices, electronic friction energy dissipation becomes particularly pronounced. However, the dynamic mechanisms underlying electronic friction energy dissipation remain unclear due to the ultrafast timescales of electronic behavior. Here, the ultrafast dynamics of electronic friction energy dissipation in monolayer WS