We develop a signaling game model of investment to explore the effects of ambiguity aversion on corporate equilibrium strategies, investment dynamics, and financing decisions in incomplete markets with asymmetric information. Our analysis shows that volatility ambiguity aversion has a similar but more pronounced effect than asymmetric information, leading to higher financing costs, lower investment probabilities, and a greater likelihood of non-participation in investment. Importantly, volatility ambiguity aversion exhibits an amplifier effect, magnifying financing costs, adverse selection costs, and distortion in investment choices under asymmetric information. This increased ambiguity aversion raises the chances of inefficient separating and pooling equilibria, resulting in notable welfare losses. These findings highlight the significant impact of ambiguity aversion on strategic decision-making and equilibrium outcomes in investment, particularly in settings marked by information asymmetry and incomplete markets.