Information and communication technologies (ICT) allow employees to access work online 24/7. It may undermine employees’ well-being. By introducing concepts of online vigilance, the constant alert to online content, into job demands-resources (JD-R) theory, this study aims to investigate how ICT demands influence employees’ well-being by affecting their cognitions. Besides, the disconnection strategy’s role as a personal resource in alleviating the effect of perceived stress on subjective well-being is taken into consideration. Based on a survey among employees in media industries, the mediated negative effect of ICT demands on employees’ subjective well-being through online vigilance and stress, as well as the moderating role of disconnection were revealed. Findings suggest that ICT demands may make employees more alerted to online work-related content, thus putting more stress on them, and harming their subjective well-being. However, the disconnection strategy can be applied as a personal resource to cope with the adverse consequence. This study sheds new light on the role ICT plays in the formation of job demands and resources.