| Ceiriog | |
| Start: | 1935 |
| End: | 1974 |
| Populationfirst: | 7,632 |
| Populationfirstyear: | 1951 |
| Populationlast: | 6,818 |
| Populationlastyear: | 1971 |
| Areafirst: | 63269acres |
| Areafirstyear: | 1951 |
| Arealast: | 63269acres |
| Arealastyear: | 1961 |
Ceiriog was a rural district in the administrative county of Denbighshire from 1935 to 1974.
The rural district was formed by a County Review Order in 1935 from the merger of Chirk and Llansillin Rural districts. The district was named after the Ceiriog Valley.
The district contained nine civil parishes:
The rural district was abolished in 1974 by the Local Government Act 1972, with its area becoming part of the district of Glyndŵr, one of six districts of Clwyd.