Objectives <p>Focused-breathing and body-scan are mindfulness techniques that serve to focus attention. However, findings on their effects on attention networks have been inconsistent. The purpose of this study was to investigate the impact of a four-week mindfulness training on attention networks, utilizing behavioral measures as well as the CNV and N2 components of event-related potentials associated with the alerting, orienting, and executive control subsystems of attention.</p> Methods <p>A longitudinal randomized controlled trial was conducted with 72 participants divided into three groups: focused-breathing, body-scan, and wait-list control (24 participants each). Behavioral and electrophysiological data were collected before and after training using attention network tests.</p> Results <p>For the alerting network, both behavioral and EEG measures showed that the wait-list control group exhibited a significantly greater decrease in network efficiency than the focused-breathing group. For the orienting network, no significant differences in behavioral or EEG changes were found. For the executive control network, the focused-breathing group demonstrated significantly greater improvements in behavioral efficiency and larger reductions in N2 amplitude than the waiting-control group.</p> Conclusions <p>Supported by behavioral and EEG data, the findings revealed that four weeks of focused-breathing training enhanced the alerting and executive control networks, whereas body-scan training showed no significant effects. These results highlight the superiority of focused-breathing for improving attentional network efficiency, demonstrating that these two forms of mindfulness training may be dissociable.</p> Preregistration <p>This study is not preregistered.</p>