Werner III of Falkenstein (? - 4 October 1418) was the Archbishop of Trier from 1388 until 1418, and the Count of Falkenstein-Lich from 1407 until 1418.

Werner was the son of Count Philip VIII of Falkenstein, and was the nephew of Cuno II of Falkenstein, the Archbishop of Trier. Werner held the offices of an archdeacon of Trier, the provost of St Florin and the provost of St Paul. After his uncle abdicated in 1388, Werner was appointed the coadjutor and then archbishop by Pope Urban VI. He used the wealth accumulated by Cuno to settle feuds against Schleiden, Ehrenberg, Waldeck, Hesse-Rheinfels, and the cities of Oberwesel and St Goar. Due to the feuds, the archbishopric was ruined and bankrupted, and Werner faced strong opposition from the cathedral chapter. In 1389 they asked Pope Boniface IX to depose him but was refused.

Werner built Burg Wernerseck as new residence in 1402. At the Councils of Pisa and Constance Werner did not implement their reforms. He died in 1418 attacking St Goar, and was buried in St Kastor in Koblenz.

Preceded by:

Werner of Falkenstein

Succeeded by:

Cuno II of Falkenstein Archbishop of Trier
1388 - 1418
Otto of Ziegenhain
Philip VIII Lord of Falkenstein-Lich
1407 - 1418
to Solms