This review examines the effects of mindfulness on psychological health, focusing on empirical studies. Mindfulness, defined as nonjudgmental awareness of the present moment, has been linked to psychological well-being, including increased subjective well-being, reduced psychological symptoms, and improved behavioral regulation. The review discusses three areas of research: correlational studies showing associations between mindfulness and psychological health, intervention studies on the effects of mindfulness-based interventions, and laboratory studies on the immediate effects of mindfulness on emotional and behavioral functioning. Mindfulness is associated with positive psychological outcomes such as higher life satisfaction, agreeableness, conscientiousness, vitality, self-esteem, empathy, and optimism, and lower levels of depression, neuroticism, and rumination. It also correlates with enhanced cognitive flexibility and attentional functioning, and with neurobiological changes in brain regions involved in attention, interoception, and sensory processing. Several mindfulness-based interventions, including Mindfulness-Based Stress Reduction (MBSR), Mindfulness-Based Cognitive Therapy (MBCT), Dialectical Behavior Therapy (DBT), and Acceptance and Commitment Therapy (ACT), have been studied. MBSR has been shown to reduce anxiety, depression, anger, rumination, and general psychological distress, while improving positive affect, empathy, and quality of life. MBCT has been effective in preventing relapse in depression and improving symptoms in remitted depressed patients. DBT has been effective in reducing self-harm and suicidal behavior in individuals with borderline personality disorder, and ACT has been found to be effective in reducing symptoms of depression, anxiety, and substance use. Laboratory studies have shown that brief mindfulness interventions can have immediate effects on emotional regulation, reducing negative affect and increasing willingness to engage with unpleasant tasks. These findings suggest that mindfulness can enhance psychological well-being by increasing awareness and acceptance of internal experiences. Future research should explore the mechanisms of mindfulness interventions, the effectiveness of different mindfulness teaching approaches, and the relationship between the amount of intervention exposure and psychological benefits.This review examines the effects of mindfulness on psychological health, focusing on empirical studies. Mindfulness, defined as nonjudgmental awareness of the present moment, has been linked to psychological well-being, including increased subjective well-being, reduced psychological symptoms, and improved behavioral regulation. The review discusses three areas of research: correlational studies showing associations between mindfulness and psychological health, intervention studies on the effects of mindfulness-based interventions, and laboratory studies on the immediate effects of mindfulness on emotional and behavioral functioning. Mindfulness is associated with positive psychological outcomes such as higher life satisfaction, agreeableness, conscientiousness, vitality, self-esteem, empathy, and optimism, and lower levels of depression, neuroticism, and rumination. It also correlates with enhanced cognitive flexibility and attentional functioning, and with neurobiological changes in brain regions involved in attention, interoception, and sensory processing. Several mindfulness-based interventions, including Mindfulness-Based Stress Reduction (MBSR), Mindfulness-Based Cognitive Therapy (MBCT), Dialectical Behavior Therapy (DBT), and Acceptance and Commitment Therapy (ACT), have been studied. MBSR has been shown to reduce anxiety, depression, anger, rumination, and general psychological distress, while improving positive affect, empathy, and quality of life. MBCT has been effective in preventing relapse in depression and improving symptoms in remitted depressed patients. DBT has been effective in reducing self-harm and suicidal behavior in individuals with borderline personality disorder, and ACT has been found to be effective in reducing symptoms of depression, anxiety, and substance use. Laboratory studies have shown that brief mindfulness interventions can have immediate effects on emotional regulation, reducing negative affect and increasing willingness to engage with unpleasant tasks. These findings suggest that mindfulness can enhance psychological well-being by increasing awareness and acceptance of internal experiences. Future research should explore the mechanisms of mindfulness interventions, the effectiveness of different mindfulness teaching approaches, and the relationship between the amount of intervention exposure and psychological benefits.