The Finnish 27th Jäger Battalion (German: Königlich Preussisches Jägerbataillon Nr. 27) was an elite light infantry unit in the German Army from 1915 to 1918 which consisted mainly of volunteers of the Finnish Jäger troops.

The recruitment of the Jäger volunteers from the Russian Grand Duchy of Finland had to be secret, and was dominated by German-influenced circles, such as university students and the upper middle class. The recruitment was however in no way exclusive. The recruits were transported across Finland's western border via Sweden to Germany, where the volunteers were formed into the Royal Prussian 27th Jäger Battalion. It was a continuation and expansion of the "Boy Scout Training" (Pfadfinderkursus).