| Hernaín Arzú | |
| Fullname: | Hernaín Arzú Güity |
| Birth Date: | 13 October 1967 |
| Birth Place: | Santa Rosa de Aguán, Honduras |
| Position: | Defender |
| Years1: | 1988–1998 |
| Caps1: | 212 |
| Goals1: | 1 |
| Years2: | 1999–2000 |
| Clubs2: | Marathón |
| Nationalyears1: | 1992–1998 |
| Nationalteam1: | Honduras |
| Nationalcaps1: | 36 |
| Nationalgoals1: | 0 |
| Manageryears1: | 2003 |
| Managerclubs1: | Motagua |
| Manageryears2: | 2003 |
| Managerclubs2: | Motagua (assistant) |
| Manageryears3: | 2012 |
| Managerclubs3: | Alianza Becerra |
Hernaín Arzú Güity (born 13 October 1967) is a retired Honduran football player who made his name with the national team in the 1990s.
Arzú started his career at F.C. Motagua and played 212 matches for the club over a period of 10 years.[1] He also played for Marathón.
Arzú made his debut for Honduras in a June 1992 friendly match against Panama and has earned a total of 36 caps, scoring no goals. He has represented his country in 6 FIFA World Cup qualification matches and played at the 1995[2] and 1997 UNCAF Nations Cups[3] as well as at the 1998 CONCACAF Gold Cup.[4]
His final international was a February 1998 CONCACAF Gold Cup match against Mexico.