To provide an automatic swirl control GDI injector for improving the workability of assembling and servicing an engine, offering lighter construction and eliminating the need for an ECU control line and a swirler control device in addition.

The automatic swirl control GDI injector comprises a body and an automatic swirl control device installed in a fixed groove formed in one side at the upper part of the body for controlling a swirl amount. The automatic swirl control device has: an upper housing fixed and joined to one side at the upper part of the body; a lower housing having a through-hole formed in the center; a knob shaft installed in the through-hole of the lower housing; a vane supported by the knob shaft and installed between the bottom of the upper housing and the upper part of the lower housing; and a restoring spring installed on the knob shaft so that the knob shaft can be turned by injection pressure.