Mindfulness-oriented therapeutic methods focus on the belief that mindfulness is a fundamental healing process. Inspired by both Buddhist and Western psychological traditions, this approach is based on the notion that through the practice of mindfulness, each individual has the opportunity to connect more deeply with their own health, inner regulation, and inner wisdom. Recently, the effects of Mindfulness-Based Therapies on psychological health have been investigated in studies on individuals with various physical disorders, such as cancer. In these studies, mindfulness-based therapies were more effective in experimental groups than in control groups. In addition, it was concluded that these interventions positively affected the physical ailments of patients with cancer, such as pain, fatigue, and somatic symptoms; reduced psychological distress, such as depression, anxiety, and stress; and caused positive changes similar to posttraumatic growth and improved their quality of life. This chapter provides general information about commonly used methods, such as the Mindfulness-Based Stress Reduction Program, Mindfulness-Based Cognitive Therapy, Dialectical Behavior Therapy, Acceptance and Commitment Therapy, and Compassion-Focused Therapy, and case examples of mindfulness-based therapy techniques in working with cancer patients, application methods, and their effectiveness in depression, anxiety, fatigue, stress management, and overall quality of life in patients diagnosed with cancer.