Background　Combined　art-based　interventions　(CAIs)　are　considered　effective　treatment　options　for　older　adults　along　the　cognitive　continuum;　however,　the　neural　mechanisms　underlying　associated　changes　in　neurocognitive　performance　remain　unclear.　Thus,　we　aimed　to　investigate　the　impact　of　a　CAI　programme　in　older　adults　along　the　cognitive　continuum　and　to　understand　its　mechanism.　Methods　This　parallel-arm　randomised　controlled　trial　was　conducted　between　April　2021　and　January　2023.　Participants　were　randomised　in　a　1:1　ratio　to　either　intervention　group　(IG)　or　waitlist　control　group　(WG).　The　IG　underwent　a　16-week　CAI　programme.　Neuropsychological　assessments　and　magnetic　resonance　imaging　were　conducted　before　and　after　the　intervention.　Results　After　the　intervention,　the　IG　showed　greater　improvement　in　general　cognitive　function,　language,　and　memory　than　the　WG.　Significant　differences　were　observed　in　the　functional　connectivity　(FC)　values　in　the　temporal　and　cerebellar　anterior　lobes,　fusiform,　inferior　occipital,　and　lingual　gyri,　and　perirhinal　and　visual　cortices　between　the　groups.　Further　analyses　showed　that　FC　values　were　reduced　in　these　regions　in　the　IG.　In　addition,　changes　in　FC　values　were　positively　correlated　with　those　in　neuropsychological　test　scores　in　the　IG.　Conclusions　Our　study　suggests　that　the　CAI　programme　can　effectively　improve　general　cognitive　function,　language,　and　memory　in　older　adults　along　the　cognitive　continuum.　These　improvements　may　be　changed　due　to　decreases　in　FC　in　key　brain　regions,　deepening　the　understanding　of　the　neurocentral　mechanisms　that　act　as　a　tool　for　improving　cognitive　function.