Purpose This paper aims to assess how digital knowledge management affects technostress in workers and how that influences the organization’s sustainability. The study applied an in-depth literature review of the following concepts and dimensions, digital knowledge management (acquisition, sharing and application), technostress (techno overload, invasion, complexity, insecurity and uncertainty) and sustainability (economic, social and environmental). Design/methodology/approach After completing the literature review, an online questionnaire was developed and disseminated through social networks. The questionnaire had four sections: classification of the respondent, questions related to knowledge management, technostress and sustainability. The final sample comprises 454 responses. First, a descriptive analysis of the sample was carried out, and second, a structural equation model by the partial least squares–structural equation modeling method was conducted. Findings The results show that there is a direct and positive relationship between knowledge management and technostress. This finding means that a higher level of knowledge management of firms causes a greater level of technostress among employees. The close relationship between knowledge management and the firms’ sustainability has also been confirmed. The study results have shown that gender does not have a moderating effect on the relationships reported, as there are no significant differences. Originality/value To the best of the authors’ knowledge, this study is the first to look at digital knowledge management, assessing both the levels of employee technostress and the sustainability achieved by their organizations. Thus, this study could serve as a basis for future research. In addition, it contributes to the scarce academic literature on technostress and digital knowledge management levels.