In this study, it was aimed to determine the floristic composition of Tokatli Canyon in North West Anatolia. Plant samples were collected for two seasons. The family, life form and the floristic regions of the plant specimens were identified. A total of 102 taxa found in total belonging % 10 (10) to Asteraceae, 7% (7) to Labiatae, 7% (7) to Poaceae, 6% (6) to Ranunculaceae, 6% (6) Rosaceae and 65% (66) to other families. According to the distribution of life form, the highest rate was 58% (59), belonging to hemicriptophyte form. Among the identified species, the largest proportion of species belonged to pluriregional or unknown floristical region with 50% (51), with 31% (32) of the Euro-Siberian, 11% (11) of the Mediterranean and 8% (8) of the Irano-Turanian territory. This study is the first floristic study of Tokatli Canyon showing importance of canyon in terms of plant diversity. In the study area, 8 endemic taxa were identified constituting 7.8% of total flora. Tokatli Canyon consists of 50 families, 94 genera and 102 taxa.