A report by Newport Consulting in Australia has found that $200 billion worth of planned mining projects are in doubt.
The ABC reports falling commodity prices and surging operating costs are the major reasons why companies are becoming less optimistic about the future of the resources boom.
The report involved interviews with dozens of miners about their willingness to invest in future projects.
It found only 25% of companies are planning to invest in capital expenditure projects this year, compared with 52% last year.
David Hand of Newport says many mining companies are thinking twice about investment decisions.
"We believe that $A200 billion worth of investment is in jeopardy and in doubt," he said.
Meanwhile, the ABC reports iron ore prices continue to slump, falling on Monday to a two and a half year low.