| Harry Vermaas | |
| Birth Name: | Cornelis Hermanus Vermaas |
| Birth Date: | 23 January 1984 |
| Height: | 1.80NaN0 |
| Weight: | 108kg (238lb) |
| Occupation: | Professional rugby player |
| School: | Afrikaanse Hoër Seunskool |
| University: | University of Pretoria |
| Ru Currentteam: | USA Limoges |
| Position: | Hooker |
| Provinceyears1: | 2005–06 |
| Provinceyears2: | 2006–07 |
| Provinceyears3: | 2007–10 |
| Provinceyears4: | 2010–13 |
| Provinceyears5: | 2014- |
| Province1: | Blue Bulls |
| Province2: | Leinster |
| Province3: | Boland |
| Province4: | AS Béziers |
| Province5: | USA Limoges |
| Provinceapps1: | 2 |
| Provinceapps2: | 14 |
| Provinceapps3: | 22 |
| Provinceapps4: | 56 |
| Provinceapps5: | 14 |
| Provincepoints1: | 0 |
| Provincepoints2: | 0 |
| Provincepoints3: | 0 |
| Provincepoints4: | 15 |
| Provincepoints5: | 5 |
Cornelis Hermanus "Harry" Vermaas (born 23 January 1984) is a South African rugby union rugbymen who currently plays for USA Limoges in the French domestic Fédérale 1 competition. He is a versatile front rower who is capable of playing either at prop or at hooker and has also represented Leinster, the Blue Bulls, Boland Cavaliers, Pumas and the Springboks' Under-21 team.