| 2025 | Cy Gallion | Campbell County | 4:49.02 | Malachi Villarreal | Kemmerer | 4:37.94 | |
| 2024 | Cy Gallion | Campbell County | 4:48.90 | Malachi Villarreal | Kemmerer | 4:55.00 | |
| 2023 | Aiden Stakes | Laramie | 4:58.30 | Brady Young | Green River | 4:45.80 | |
| 2022 | Collin Fontana | Laramie | 4:50.51 | Brayden Brown | Lander | 4:49.36 | |
| 2021 | Jared Price | Cheyenne South | 4:54.44 | Brayden Brown | Lander | 4:53.29 | |
| 2020 | Jared Price | Cheyenne South | 4:56.05 | Brayden Brown | Lander | 4:59.67 | |
| 2019 | J.R. Albers | Thunder Basin | 4:56.11 | Nick Kulow | Lander | 4:56.71 | |
| 2018 | Jackson Mugg | Cheyenne East | 4:51.14 | Nick Kulow | Lander | 4:58.87 | |
| 2017 | Darwin Anderson | Rock Springs | 4:42.07 | Caleb Huelskamp | Lander | 5:02.59 | |
| 2016 | Jackson Mugg | Cheyenne East | 4:52.76 | Caleb Huelskamp | Lander | 5:11.44 | |
| 2015 | Kayden Harbison | Rock Springs | 4:42.00 | Ben Wetzel | Powell | 5:06.34 | |
| 2014 | Kayden Harbison | Rock Springs | 4:38.93 | Ben Wetzel | Powell | 5:00.47 | |
| 2013 | Kayden Harbison | Rock Springs | 4:48.73 | Drew Gramlich | Lander | 5:07.96 | |
| 2012 | Nick Dillinger | Campbell County | 4:58.25 | Neil Medders | Buffalo | 5:09.80 | |
| 2011 | Garrett Koehler | Cheyenne Central | 4:46.69 | Stephen Powers | Lyman | 4:59.16 | |
| 2010 | Alek Anderson | Green River | 4:54.68 | Stephen Powers | Lyman | 4:57.94 | |
| 2009 | Andrew Huddleston | Campbell County | 4:45.22 | Stephen Powers | Lyman | 5:07.04 | |
| 2008 | Trevor Andersen | Cheyenne Central | 4:58.46 | Stephen Powers | Lyman | 5:13.43 | |
| 2007 | Joe Wood | Cheyenne Central | 4:58.39 | Austin Hofmann | Rawlins | 5:08.30 | |
| 2006 | Trevor Andersen | Cheyenne Central | 4:56.71 | Sam Spade | Buffalo | 5:05.62 | |
| 2005 | Kolbin Bertilson | Laramie | 5:01.99 | Brian Johnson | Kemm | 5:14.25 | |
| 2004 | Alex Anderson | Cheyenne Central | 4:51.25 | Brian Johnson | Kemm | 5:15.45 | |
| 2003 | Alex Anderson | Cheyenne Central | 4:49.61 | Micah Schuster | Lander | 5:08.28 | |
| 2002 | Alex Anderson | Cheyenne Central | 4:51.33 | Micah Schuster | Lander | 5:04.34 | |
| 2001 | Trevor Haley | Kelly Walsh | 4:39.39 | Eric Moxley | Lander | 4:48.17 | |
| 2000 | Trevor Haley | Kelly Walsh | 4:41.38 | Mike Pryor | Lander | 5:02.41 | |
| 1999 | Zach Mueller | Laramie | 4:53.28 | Eric Moxley | Lander | 4:57.19 | |
| 1998 | Jon Christianson | Campbell County | 4:58.38 | Guy Fulfer | Worland | 4:50.19 | |
| 1997 | Jon Christianson | Campbell County | 5:03.75 | Jake Cook | Buffalo | 4:53.19 | |
| 1996 | Chris Carter | Kelly Walsh | 5:00.09 | Jake Cook | Buffalo | 4:50.11 | |
| 1995 | Rob Yovich | Laramie | 4:57.18 | Jake Cook | Buffalo | 4:58.66 | |
| 1994 | Clint Beck | Evanston | 5:18.58 | Duke DeClue | Lander | 5:10.45 | |
| 1993 | J.J. Bay | Campbell County | 4:50.19 | Toby Trainer | Douglas | 5:03.44 | |
| 1992 | J.J. Bay | Campbell County | 5:02.18 | Toby Trainer | Douglas | 5:08.01 | |
| 1991 | J.J. Bay | Campbell County | 4:51.60 | Doug Miyamoto | Rawlins | 5:05.14 | |
| 1990 | Chris Morgan | Rawlins | 4:47.26 | Tim Kauls | Buffalo | 5:20.70 | |
| 1989 | Chris Morgan | Rawlins | 4:45.55 | Jory Turk | Powell | 5:13.13 | |
| 1988 | Sean Tesoro | Evanston | 4:56.37 | Jory Turk | Powell | 5:08.69 | |
| 1987 | Walt Eggers | Laramie | 4:53.63 | Sean Tesoro | Evanston | 5:01.50 | |
| 1986 | Walt Eggers | Laramie | 4:57.33 | Brad Crompton | Evanston | 5:15.79 | |
| 1985 | Walt Eggers | Laramie | 4:54.89 | Brad Crompton | Evanston | 5:20.20 | |
| 1984 | Mark Miller | Laramie | 4:42.68 | Dana Penn | Douglas | 5:27.23 | |
| 1983 | Tim Hanson | Campbell County | 5:24.017 | Jens Swenson | Glenrock | 5:55.822 | **races in meters |
| 1982 | Russ Ashenden | Laramie | 4:54.408 | Ron Chapin | Big Piney | 5:22.646 | |
| 1981 | Rob Bress | Laramie | 4:56.096 | Ron Chapin | Big Piney | 5:12.699 | |
| 1980 | Jon Wolf | Rawlins | 5:38.240 | Ron Chapin | Big Piney | 5:59.147 | **races in meters |
| 1979 | Alan Fisser | Laramie | 4:52.601 | Rick Barker | Newcastle | 6:00.782 | **Class A races in meters |
| 1978 | Alan Fisser | Laramie | 4:52.39 | Rick Barker | Newcastle | 6:00.907 | **Class A races in meters |
| 1977 | Alan Fisser | Laramie | 5:10.808 | Rick Barker | Newcastle | 5:58.926 | |
| 1976 | Dale Stadler | Laramie | 5:21.86 | Gary Gonder | Green River | 5:52.08 | |
| 1975 | Gary Frickey | Sheridan | 5:15.43 | Gary Gonder | Green River | 6:08.08 | |
| 1974 | Gary Frickey | Sheridan | 5:17.00 | Kevin Goglio | Green River | 5:59.30 | |
| 1973 | Gary Frickey | Sheridan | 4:16.5 | Marty Knox | Thermopolis | 4:27.0 | ***was 400 freestyle |
| 1972 | Kevin Tripp | Cody | 4:21.5 | Bruce Roumell | Glenrock | 4:43.0 | ***was 400 freestyle |
| 1971 | Dave Broyles | Cheyenne East | 4:05.7 | Lloyd Hildebrand | Newcastle | 4:43.2 | ***was 400 freestyle |
| 1970 | Dave Broyles | Cheyenne East | 4:23.2 | Lloyd Hildebrand | Newcastle | 4:58.3 | ***was 400 freestyle |
| 1969 | Rick Basford | Laramie | 4:15.1 | - | - | - | ***was 400 freestyle |
| 1968 | Greg Bentley | Powell | 4:34.4 | - | - | - | ***was 400 freestyle |
| 1967 | Jim Haworth | Powell | 4:27.6 | - | - | - | ***was 400 freestyle |
| 1966 | Jim Haworth | Powell | 4:37.8 | - | - | - | ***was 400 freestyle |
| 1965 | Jim Haworth | Powell | 4:49.6 | - | - | - | ***was 400 freestyle |
| 1964 | Gus Spohn | Cheyenne Central | 4:45.8 | - | - | - | ***was 400 freestyle |
| 1963 | Barry Braa | Powell | 4:53.4 | - | - | - | ***was 400 freestyle |
| 1962 | Barry Braa | Powell | 4:55.8 | - | - | - | ***was 400 freestyle |
| 1961 | Barry Braa | Powell | 5:12.0 | - | - | - | ***was 400 freestyle |
| 1960 | Ralph Helms | Natrona | 5:05.8 | - | - | - | ***was 400 freestyle |
| 1959 | Bob Berger | Powell | 5:02.2 | - | - | - | ***was 400 freestyle |
| 1958 | Bob Berger | Powell | 5:05.2 | - | - | - | ***was 400 freestyle, first year |
| before 1958 | Not competed | | | - | - | - | |