Background: The aim of this study was to examine the content validity of the construct of worker quality of life for the subsequent development of an assessment instrument. The present study used a qualitative approach involving a focus group of experts in worker quality of life who provided data regarding attitudes, opinions, perceptions and behaviors related to worker health and quality of life. The focus group discussion constituted the first step toward the elaboration of a specific questionnaire for the assessment of this construct. Method: This was a qualitative study, using a focus group design, involving experts in worker health and quality of life. Bardin content analysis was used to identify domains and subdomains of worker quality of life. Results: The focus group defined worker quality of life in terms of five domains: physical, environmental, psychological, social and occupational. Each of these domains was further divided into several subcategories, all of which were considered by the expert panel to constitute the construct of worker quality of life. Conclusões: The present study yielded a comprehensive definition of the concept of worker quality of life, which will be used to develop questions for an assessment instrument and may serve as a basis for future studies on the topic.