"After losing against Sport Lausanne, coach Bernard Challandes took the confidence test and asked if the players were 100 percent behind him," the club said in a statement.
"The team told the coach that a large majority were against a future with him. Therefore, the coach accepted the consequences and has given up his position."
The 61-year-old coach has done the rounds of Switzerland's top clubs, coaching Young Boys, Servette Geneva, FC Zurich, FC Sion and Neuchatel Xamax in his lengthy career.
Thun, from the small lakeside town of the same name, are ninth in the 10-team Swiss Super League after a six-match winless run.
The club rose from third tier amateur football in the 1990s to the heady heights of the Champions League in 2005/06, only to drop back down to the second tier two seasons later.
They have finished the last two seasons in fifth after being promoted again in 2009/10.
FC Basel, FC Lucerne and Servette Geneva have changed coaches once each this season while Sion have parted company with two coaches.
- Sports & Recreation
- Servette Geneva
- Bernard Challandes