Blackstone raised just $25bn of an expected $32bn in the last quarter as profit fell by more than a third.
The alternative asset manager is now keeping its powder dry for future deals at more favourable rates.
Blackstone said its net profit from the sale of assets had fallen by 36% to $259.4m in the three months to the end of September.
It raised $25bn from investors over the same period, falling short of analysts’ forecasts of $32bn, and deployed $12.4bn of capital.
Chair and chief executive Stephen Schwartzman said the group had built up a record level of unused capital of $200bn.
