Background: The prevailing theoretical models of posttraumatic growth (PTG) are fundamentally cognitive. However, few studies have examined the relationship of PTG with metacognitive beliefs, self-focused attention and trauma-related attitudes toward the world and oneself. These cognitive constructs might influence in the development of PTG. The aim of the study was to examine the relationship of PTG with dysfunctional metacognitive beliefs, dysfunctional self-focused attention (self-absorption), and dysfunctional trauma-related attitudes. Method: A sample of 250 adults (58.8% women; average age = 41.9 years) who had suffered a traumatic event in the past (on average, 14.5 years prior to the study) completed tests measuring those three cognitive constructs, symptoms of posttraumatic stress and depression, optimism, and PTG. Results: Multiple regression analyses revealed significant linear and inverted U-shaped relationships between some dimensions of PTG and negative beliefs about the uncontrollability and danger of worry, cognitive self-consciousness, private self-absorption, and dysfunctional traumatic attitudes related to chronification of distress. However, the variables that showed the greatest and most consistent relationships with PTG were the number of traumatic events suffered and posttraumatic stress symptomatology and, to a lesser extent, optimism and depressive symptomatology. Conclusion: The results highlight the important role that cognitive factors play in PTG. More specifically, the results underline the important role of people's basic attitudes toward themselves and the world, as well as the role of self-focused attention and metacognitive beliefs. The results also support the hypothesis that a certain degree of emotional distress may be a necessary precondition for PTG.