Note: LoLPortal is no longer being actively updated as I've joined Riot Games to work on their esports web initiatives. See this blog post for more information. This table is based on data from 929 matches between professional League of Legends teams across all three major regions in recent tournaments from IPL 5 onwards. You can click on the table headings to sort by a particular statistic.
http://lolportal.net/Champions/
According to LoLking (http://www.lolking.net/champions/), the current top 10 win-rate champions in order: 1  Amumu (14.29% popularity, 55.59% win rate) 2  Fiora (7.9% popularity, 54.55% win rate) 3  Rammus (4.65% popularity, 54.43% win rate)  Warwick (14.46% popularity, 54.31% win rate)
http://forums.na.leagueoflegends.com/board/showthread.php?t=4818325
1 That this champion is a good champion to pick in every scenario; 2  That a top 10 win rate champion is necessarily better than a top 20; and.  That this champion will win their lane match-up more often then not.
http://www.nerfplz.com/2014/06/win-rates-what-do-they-mean.html
Welcome to the Forum Archive! Years of conversation fill a tonne of digital pages, and we've kept all of it accessible to browse or copy over. Whether you're looking for reveal articles for older champions, or the first time that Rammus rolled into an OK thread, or anything in between, you can find it here. When you're finished, check out Boards to join in the latest League of Legends discussions. GO TO BOARDS.
http://forums.eune.leagueoflegends.com/board/showthread.php?t=578782
According to LoLking (http://www.lolking.net/champions/), the current top 10 win-rate champions in order: 1  Amumu (14.29% popularity, 55.59% win rate)  Fiora (7.9% popularity, 54.55% win rate)
http://forums.na.leagueoflegends.com/board/showthread.php?t=4818325
According to LoLking (http://www.lolking.net/champions/), the current top 10 win-rate champions in order: 1  Amumu (14.29% popularity, 55.59% win rate) 2  Fiora (7.9% popularity, 54.55% win rate)  Rammus (4.65% popularity, 54.43% win rate)
http://forums.na.leagueoflegends.com/board/showthread.php?t=4818325
Riot games in constantly looking to improve the balance of the game. Naturally there will be some champions that do better in particular patches than other. You can check out what champions have the highest win rates at any time here: Charts & Statistics - League of Legends. You can narrow the results by region, map, time and rank. For example: over the last week in North America in Bronze ranked solo queue, Amumu has the highest win rate. That being said, don't just pick whatever champion is highest.
https://www.quora.com/What-are-the-best-champions-to-get-out-of-bronze-in-League-of-Legends
you should probably worry less about the highest winrate champ and more about your strategies on your current champs as well as how appropriate your champ is for your current level of play (after considering ones teammates) There is going to be a yearly pre-worlds metashift and post-worlds meta shift.
http://forums.na.leagueoflegends.com/board/showthread.php?t=4818325
Of course there are some champions that are easier to carry with then others, in my experience assassins are the best to win games in bronze because people don't know how to play against someone with high damage that almost one shots them, in higher elos people know how to play against them, but not in low elo.
https://www.quora.com/What-are-the-best-champions-to-get-out-of-bronze-in-League-of-Legends
According to LoLking (http://www.lolking.net/champions/), the current top 10 win-rate champions in order: 1  Amumu (14.29% popularity, 55.59% win rate) 2  Fiora (7.9% popularity, 54.55% win rate) 3  Rammus (4.65% popularity, 54.43% win rate) 4  Warwick (14.46% popularity, 54.31% win rate)  Rumble (1.43% popularity, 54.17% win rate)
http://forums.na.leagueoflegends.com/board/showthread.php?t=4818325
highest win rates lol
The highest win rates of League of Legends is of Amumu. Amumu has the highest win rate at the League of Legends.