Ffrwd yr Ydfran is a waterfall on Nant Troed-y-rhiw in the upper Ystwyth Valley of mid-Wales, located at grid reference SN 82267 76349 (52. 372°N, 3. 731°W).

The stream descends approximately 90 metres down the steep valley side, which rises to around 500 metres in this area.

Rather than forming a single dramatic plunge, Ffrwd yr Ydfran tumbles in a cascading style without any one sufficiently distinct drop to stand out on its own.

It is one of several waterfalls visited on an upper Ystwyth waterfall walk that also takes in Nant y Cae Falls, Nant Cwm-du Falls, and Nant y Gwaith Falls.