Malignant diseases, as the second leading cause of death, represent one of the greatest public health problems today in childhood and adulthood. Learning about the diagnosis affects the individual's daily life and family dynamics, as intense emotions arise in the person. This thesis is dedicated to describing the coping mechanisms for individuals with malignant diseases, with an emphasis how persons with malignant diseases cope with the diagnosis and the challenges during psychological adjustment to the new situation. In their coping with the malignant diseases, persons use various strategies and interventions based on the dimensions of the coping mechanisms. The importance of psychosocial oncology is emphasized, with a key role in the comprehensive understanding of the persons with malignant disease, reducing negative attitudes and stigma. It is based on providing emotional and psychological support to the persons. One of the main focuses of psychosocial oncology is analyzing emotional reactions during coping with malignant diseases, so attention is given to the psycho-emotional characteristics of persons, including diseases of adults, children and parents. As well, the importance of providing psycho-emotional support in working with persons with malignant diseases is also highlighted, as well as the importance of multidisciplinary team cooperation, including educated professionals, especially in treating severe malignant pain and consequent palliative care. The role of support programs, screening programs, associations, foundations and initiatives aimed at raising awareness among the population and reducing mortality rates is mentioned. The effectiveness of coping mechanisms is essential for maintaining the quality of life for persons with malignant diseases. However, there is a need for further development of support and resources, as well as tailored therapeutic approaches to facilitate persons' coping with the diseases and improve their overall well-being.