Fischbach bei Dahn is a municipality in Südwestpfalz district, in Rhineland-Palatinate, western Germany.

The hollow in which Fischbach lies is surrounded by hills rising to around 400 metres above sea level. The highest hills in the general area are: to the northeast the Große Eyberg (514 m) and, to the south, beyond the French border, the Maimont (512 m). The summits of both hills are about four kilometres from the village.