| State: | KY |
| Type: | KY |
| Route: | 644 |
| Map Custom: | yes |
| Map Notes: | KY 644 highlighted in red |
| Length Mi: | 2.821 |
| Direction A: | West |
| Terminus A: | near Louisa |
| Direction B: | East |
| Terminus B: | near Louisa |
| Counties: | Lawrence |
| Previous Type: | KY |
| Previous Route: | 643 |
| Next Type: | KY |
| Next Route: | 645 |
Kentucky Route 644 (KY 644) is a 2.821adj=midNaNadj=mid state highway in Lawrence County, Kentucky, that runs from KY 2565 to KY 2 south of Louisa.