Investors could be left to fend for themselves in the face corporate wrongdoing or crisis, the corporate watchdog has warned, as budget cuts strip it ability to monitor parts of the market.

Australian Securities and Investment Commission chairman Greg Medcraft told a Senate estimates hearing that there would no longer be a corporate cop "on every corner" and that investors would need to take more responsibility for themselves.

ASIC chief Greg Medcraft has told a Senate committee budget cuts will hurt its ability to monitor markets effectively. Credit:Michel O'Sullivan

Mr Medcraft said the areas most heavily hit by budget cuts would be ASIC's markets and consumer surveillance teams, including the monitoring of prospectuses and credit, deposit taking and insurance monitoring.

He said its registry business would also be downsized.