While first-wave Vietnamese immigrants adapted well to life in the United States, subsequent immigrants have had greater adjustment difficulties, including more evidence of psychological distress. This study aimed to analyze psychosocial adaptation differences among three generations of recent Vietnamese immigrants, as well as to examine predictors of mental distress in the sample as a whole. A community sample of 184 recent Vietnamese immigrants, categorized as either elderly, middle-aged, or young adults, was assessed for levels of psychological distress, including depression, anxiety, and PTSD, as well as family conflict, dissatisfaction with life in the U.S., acculturation and biculturalism, social support, coping, and premigratory stressors. Young Vietnamese adults were most acculturated, most bicultural, and reported themselves as healthiest and least depressed. They were most often working, least often on welfare, and had the highest family income. However, they also reported most dissatisfaction with their current lives in the U.S. and most family conflict. Regression analysis explaining approximately one-quarter of the variance in mental distress implicated current dissatisfaction with and lack of adjustment of life in the United States, as well as greater acculturation and increased family conflict. Although young adults scored significantly higher than other generations on most of the risk factors for psychological distress, they appeared to be buffered against poorer mental health outcomes by factors of generation and perceived positive overall well-being. In terms of testing a predictive model of psychological distress, this study found current adjustment factors significantly more important in determining mental health outcomes than premigratory stressors such as war-related traumas.