This paper investigates corporate investment and financing under volatility ambiguity within a moment-constrained variational preferences framework. Volatility ambiguity erodes firm value and distorts the marginal value of cash asymmetrically. Driven by precautionary motives, heightened ambiguity aversion increases the external financing-to-capital ratio and the payout boundary, thereby crowding out capital expenditure. Crucially, whereas drift ambiguity accelerates asset sales in the presence of refinancing options, volatility ambiguity discourages divestments during cash shortages. These findings provide a theoretical rationale for the emerging-market underinvestment puzzle and characterize corporate policies consistent with observed SME financing behaviors.