| Name | Gender | Pronounced | Usage | Popularity |
|---|---|---|---|---|
| Glyn | - | Welsh | ||
| Glyndwr | - | Welsh | ||
| Glynis | - | Welsh | ||
| Glynn | - | Welsh | ||
| Goronwy | - | Welsh, Welsh Mythology | ||
| Govannon | - | Welsh Mythology | ||
| Griffith | - | Welsh | ||
| Grigor | - | Welsh, Bulgarian, Macedonian, Armenian | ||
| Gronw | - | Welsh | ||
| Gruffud | - | Welsh | ||
| Gruffudd | GRIF-idh | Welsh | ||
| Gruffydd | GRIF-idh | Welsh | ||
| Grwn | - | Welsh | ||
| Guto | GI-taw | Welsh | ||
| Gwalchmei | - | Welsh Mythology |