Canlyniadau etholiadau ar gyfer Gorllewin Treffynnon

 Plaid Cymru - The Party of Wales Ennill Gareth Roberts was wedi'i ethol with a majority of 36%. Cafodd cyfanswm o 681 o bleidleisiau eu bwrw, representing a turnout of 37% .

Table of main parties and election candidates retaining deposit

Ymgeisydd etholiad	Plaid	Nifer	%	Statws
Gareth Roberts	Plaid Cymru - The Party of Wales	395	58%	Wedi'i ethol
Ed Watkinson	Labour / Llafur	150	22%	Heb ei ethol
Peter York	Independent / Annibynnol	136	20%	Heb ei ethol