General Objective -Analyze the correlations between stress and workload of nursing professional at a public hospital in the city of Teresina, Piauí. Methods: Descriptive, cross-sectional, correlational, quantitative study performed at a public general hospital in the city of Teresina (Piauí), between January and April and September to November of 2013. In the first stage the ramdom sample, consisted of 145 nursing professionals, to whom was applied Section 1 of the Risk assessment guide in workplace questionnaire. In the second stage, the sample was composed of 93 professionals, who were submitted to the Adult stress symptom inventory (ISSL). The cortisol concentration quantity was determined using the Salivary Assay Kit from Salimetrics in 84 nursing professionals. The research was approved by the Research Ethics Committee. The data Analysis was performed through descriptive and inferential statistics using the Statistical Package for Social Science (SPSS) version 18.0. Results: 92,4% of the nursing professionals were female, 52,4% married, mostly in the age group between 41-50 years old (34,5%), having the average age of 44,4 years old. 60 of them were nurse technicians (41,4%), 13,1% stated working in the sterilization hub and 11,7% in operating rooms or postanesthesia care unit. As to their employment contract, 81,4% mentioned being state workers, however 17,9% of them affirmed having other kinds of contract. The day shift is performed by 56,6% of these professionals, followed by 29,7% of regular working days, with a total amount of 70,4% who work on shifts (day and night).Having 30 hours or less of work per week was mentioned by 69,7%; however 33,1% worked in other hospital facilities; the amount of pay to 54,5% was between 1 and 2 monthly minimum wage; 55,9% had just one job and 44,1% had from two to four jobs. The perceived risk factors in workplace by the nursing professionals in descending order were: risk of contracting infections/disease (77,2%), exposure to biological risk (68,3%), lesion due to perforating-cutting material (55,9%), exposure to hepatitis virus (55,1%), exposure to HIV virus (53,8%) and risk due to work overload (53,8%). The most frequent perceived health problems (provoked/ aggravated) related to work were: varicose veins (56,5%), low back pain (46,9%), stress/depression (41,4%) and lesions due to accidents (32,4%). When filling the ISSL, 93 questionnaires were obtained, from which 65 professionals showed stress symptons, although most of them (57) were in the resistance stage. The measured salivary cortisol levels ranged from 0,061mg/dl to 0,849mg/dl, with a few samples beyond normality. It was found a correlation between the workload of over 30 hours per week and stress. Conclusion: The use of salivary cortisol can help detect deleterious conditions generated by chronic occupational stress in nursing professionals, contributing to the early recognition of these conditions and to the adoption of preventive measures which permit assuring the health service quality and the balance bet...