Children's football matches are being spoiled by bad behaviour from coaches, parents and players, with club's websites also being cited as 'a dangerous tool', reports the BBC.
Cardiff and District League secretary Robin Davies said there had even been racial abuse allegations involving children this season.
League officials are looking at calling a meeting of all the clubs. The Football Association of Wales (FAW) said it was very concerned about poor behaviour, but it was a wider problem for society than just for the sport.
Cardiff and District Association Football League features some 3,800 children from under-eight to under-16 level, and about 1,000 adult players.
Mr Davies described behaviour as probably the worst he had ever known and said: "We've got an ongoing problem with the attitude of parents and the attitude of managers, which rubs off on the kids.
"We've never had racial abuse before and we've had two allegations this year. We've been getting friction between coaches. We've got a league management meeting (Tuesday) and we will have a chat about it and see what we're going to do and where we're going to go."
He said one option was to call a meeting of all the clubs to try to encourage an improvement in behaviour. Other incidents included parents verbally abusing referees and parents making "unacceptable" comments to children while they were playing.
Mr Davies said although such incidents tended to be "isolated", he had noticed more problems creeping into the game.
"Gradually, it [behaviour] has been deteriorating over the years. I've been here since 1982 and we didn't have these problems then," he said. I don't know whether it's society in general which is causing the problems. We've had incidents over the last two years at all the age groups."
He added: "Where possible, the league will take sanctions. Anything that's proved, individuals will see themselves removed."
He added that team websites could also be a source of trouble, with coaches making inappropriate comments on them.
"Websites are a dangerous tool. Comments can turn up on there which can be objectionable," he said.
"A lot of it is running down referees or sometimes hyping kids up for the next match in an unacceptable way."