| Election Name: | 1984 Plaid Cymru presidential election |
| Type: | presidential |
| Ongoing: | no |
| Previous Year: | 1981 |
| Next Year: | 1991 |
| 1Blank: | First round |
| 2Blank: | Percentage |
| 4Blank: | Percentage |
| Candidate1: | Dafydd Elis Thomas |
| 1Data1: | 1,570 |
| 2Data1: | 53.18 |
| Candidate2: | Dafydd Iwan |
| 1Data2: | 1,382 |
| 2Data2: | 46.81 |
| President (Leader) | |
| Before Election: | Dafydd Wigley |
| After Election: | Dafydd Elis Thomas |
The 1984 Plaid Cymru presidential election was held following the resignation of Dafydd Wigley, who had led the party since 1981, on the grounds of his caring commitments linked to his children's health conditions.
The contest was between Meirionnydd Nant Conwy MP Dafydd Elis Thomas and Gwynedd-based politician Dafydd Iwan.
The contest was won by Dafydd Elis Thomas [1] with the result being announced at Plaid Cymru's conference in Lampeter on Saturday 27 October 1984,[2] Thomas went on to serve until he stood down in October 1991.[3] [4]