The unions want a moratorium on job losses, and a ban on dividends
Rail unions are to ask the government to stop operators cutting jobs and paying dividends to shareholders.
The unions will tell Transport Secretary Geoff Hoon that companies are using the recession as an excuse for cuts being made to protect profits.
The recession has slowed growth in passenger numbers, leaving some train companies struggling financially, and hundreds of rail jobs are being cut.
The government says it is monitoring the industry's financial health.
After large fare rises this year, possible reductions next year could further hit revenues, says BBC transport correspondent Tom Symonds.
Some companies pay large amounts to the government for rail franchises, contracts which ministers say they would step in to renegotiate if a franchise risked collapse.
The Rail Maritime and Transport (RMT) union, the Transport Salaried Staffs Association and Aslef will warn Mr Hoon of cuts to jobs and services at an "alarming rate".
RMT general secretary Bob Crow said: "The companies are protecting their profits while those who run the services and who keep the tracks safe face the prospect of being dumped on the dole queue.
He added: "It seems strange that the government is putting taxpayers' money into an industry, and then the industry's sacking people, putting them on the dole queues and the taxpayer's picking up the money for the dole queues.
"It is critical for the future of the rail industry that the government intervene now to stop the jobs massacre and to call to account the private companies who have bled billions in profits and subsidies out of the British taxpayer," he said.
The unions will also warn of a possibility of "massive" increases in unregulated fares.