A fire extinguishing spray nozzle connected to a vertical pipeline includes a nozzle body with a plurality of micro apertures formed on a lower inner circumference thereof, and a nozzle cap connected to the nozzle body and having a guide line and orifices. The orifices of the nozzle cap communicate with a chamber formed between the nozzle body and nozzle cap, so that water supplied from the vertical pipeline flows to the orifices through a guide line. The nozzle body has a female threaded portion on an inner circumference of a connecting line, and the nozzle cap has a male threaded portion on a protruded portion thereof, so that the nozzle cap is threadedly engaged to the nozzle body.