BBC Sport Wales has been told that players' agents are taking nearly £1m per annum from the four Welsh regions.
The claim, made by two senior regional officials, comes in the wake of a number of high-profile transfers involving the four Welsh sides.
The 72 Football League clubs spent just over £7.5m in such fees last season.
There has been no official confirmation of the figures, but the Welsh Rugby Union are concerned and are trying to get a clearer picture of the situation.
The Union is meeting the four regions on Tuesday, and this issue will definitely be on the agenda
"The Union would be worried about any money being paid out that doesn't go into the sharp end of the game and doesn't add value," WRU group chief executive Roger Lewis told BBC Wales.
"Talented players need the proper advice, but we have to make sure that this is being handled in the right way.
"The Union is meeting the four regions on Tuesday, and this issue will definitely be on the agenda."
Former Ospreys regional rugby manager Derwyn Jones disputed the £1m figure and suggested that agents' fees paid by the west Glamorgan region during his tenure were between £100,000 and £150,000 per annum.
Ex-Wales captain Gwyn Jones told BBC Wales' Scrum V rugby programme that the issue of agents was a tricky subject.
The majority of players do not need an agent, just the elite
Ex-Wales captain Ieuan Evans
"Agents have crept into the game slowly - they are a part of professional sport and have a role to play," said the former flanker.
"But I would like to see an independent body working on behalf of the players instead.
"The competitiveness of the Welsh internal market for players has been increased by a ruling for next season that the regions are only allowed six foreigners."
Union central contracts have been suggested as a possible answer to the problem, but another former national captain, ex-Wales and Lions wing Ieuan Evans, does not believe that is the complete solution.
"It may sort out the internal market, but Scotland has central contracts and they have seen a player exodus to England and France, where budgets are so much larger," Evans told BBC Sport Wales.
Phillips is one of the players linked with big-money moves this year
"There has been talk for years of a draft system between the Welsh regions, to strengthen areas where particular sides are weak.
"Perhaps that needs to be introduced, because the gentleman's agreement clearly isn't working.
"The money being spent on agents is a concern, but I'm not sure what can be done about it in a professional sport.
"I would say that the majority of players do not need an agent, just the elite like Mike Phillips - his agent has come into his own lately [with the expected big-money move to the Ospreys].
"I'd like to see the vast majority have the Professional Rugby Players' Association help them through their contractual arrangements with the Union.
"That, and the advice of a good solicitor and accountant, is all they should need."