| Ewald van der Westhuizen | |
| Birth Date: | 3 April 1990 |
| Birth Place: | Ladysmith, South Africa |
| Weight: | 1140NaN0 |
| School: | Hoërskool Voortrekker, Bethlehem |
| University: | University of Johannesburg |
| Position: | Prop |
| Youthyears1: | 2008 |
| Youthyears2: | 2010 |
| Years1: | 2013–2021 |
| Apps1: | 77 |
| Points1: | 25 |
| Years2: | 2015 |
| Apps2: | 5 |
| Points2: | 0 |
| Years3: | 2018–2019 |
| Clubs3: | → |
| Apps3: | 4 |
| Points3: | 0 |
| Years4: | 2019–2020 |
| Clubs4: | Enisei-STM |
| Apps4: | 5 |
| Points4: | 0 |
| Amatyears1: | 2012–2013 |
| Amatapps1: | 8 |
| Amatpoints1: | 0 |
| Clubupdate: | 27 December 2021 |
Ewald 'Kop' van der Westhuizen (born 3 April 1990 in Ladysmith, South Africa) is a South African rugby union player for in the Currie Cup and in the Rugby Challenge. His regular position is prop.
At secondary school level, he represented his local provincial side, the, at the Under-18 Craven Week tournament in 2008. The same year, he also played for the side in the Under-19 Provincial Championship.
He moved to Johannesburg, where he represented the side in the 2010 Under-21 Provincial Championship, making a solitary appearance. His big break came during the 2013 Varsity Cup competition; he was the first-choice tighthead prop for, starting all eight their matches as they reached the semi-final of the competition.
His performance in the Varsity Cup resulted in Kimberley-based side drafting him into their side when they had an injury crisis during the 2013 Currie Cup Premier Division season. His first class debut and only appearance for them during that competition came when he started their home match against the .
He joined the side on a full-time basis in 2014. He played in all ten of their matches during the 2014 Vodacom Cup competition – starting nine of those – as the won the competition for the fifth time. He scored his first senior try in their Round Five match against former side and scored two tries in a four-minute spell in the second half to help Griquas secure a convincing 84–15 victory over the in the Quarter Finals of the competition. He played all 80 minutes of the final, helping his side to a 30–6 victory over the .
He made four substitute appearances for Griquas during the 2014 Currie Cup qualification tournament, helping his side qualify for the 2014 Currie Cup Premier Division.