The technological growth observed in the health assistance sector has been causing a direct impact on the consumption of work force in nursing, and this is being reflected in assistance costs. The use of studies on cost in the nursing practice allows the nurse to measure the available resources and to make decisions based on the best scientific evidence, ensuring the quality of assistance. Objectives: To identify the knowledge on costs of nursing and to present the levels of evidence in studies on cost in the national nursing literature. Method: Integrative review of literature, using LILACS, MEDLINE and SCIELO for the selection of articles, which constituted 29 publications. Results: 59% of the studies referred to the costs related to the clinical practice. The following cost variables were found: materials, medicines, and hours of work. The studies were classified as level six of evidence, with the predominance of descriptive quantitative studies undertaken in the hospital setting. The evidence point to the lack of knowledge on costs among nursing professionals and students, few reference to the classification of cost variables, worry of nurses in relation to the quality of care provided by technical staff, and lack of cost management by nurses.