The　tunnel　construction　environment　is　complex,　and　workers’　cognitive　load　directly　affects　safety　and　efficiency,　making　a　dynamic　assessment　urgently　needed.　This　study　aims　to　explore　the　cognitive　load　of　tunnel　construction　workers　under　different　working　environments　using　EEG　technology.　In　the　experimental　design,　subjects　adapted　to　the　virtual　reality　(VR)　environment　and　received　instructions　before　wearing　a　wireless　EEG　system　and　VR　equipment　to　begin　the　formal　experiment.　Each　subject　underwent　four　rounds　of　experiments,　corresponding　to　four　different　scenarios:　control,　night　shift,　noise,　and　confined　space.　Each　round　included　three　tasks　of　low,　medium,　and　high　difficulty.　Analysis　of　EEG　data　showed　that　tunnel　construction　tasks　in　different　environments　significantly　affected　cognitive　load,　especially　during　night　shifts　and　in　confined　spaces,　with　cognitive　load　increasing　significantly　with　task　difficulty.　The　results　provide　a　theoretical　basis　for　optimizing　the　management　of　tunnel　construction　environments　and　task　design.　©　2025　by　the　authors.