The　use　of　mobile　phones　in　driving　is　one　of　the　leading　causes　of　driving　distraction,　which　has　caused　a　large　number　of　traffic　collisions.　The　conversion　of　dual　tasks　happens　when　a　driver　interacts　with　the　navigation　system　or　makes　a　phone　call　while　driving,　and　the　execution　of　the　latter　task　could　be　affected　by　the　former　one.　This　study　explores　the　relationship　between　smartphone　addiction　and　phone　use　behavior　while　driving　and　the　characteristics　of　drivers　with　high　and　low　smartphone　addiction　in　driving　task　conversion.　A　total　of　150　college　students　were　tested　using　college　students＇　Smartphone　Addiction　Scale　Score　(SAS-C)　and　Questionnaire　on　Smartphone　Usage　While　Driving,　and　the　top　33%　and　bottom　33%　in　SAS-C.　A　total　of　43　students　participated　in　the　experiment　in　which　the　conversion　of　tasks　was　involved.　The　results　showed　that:　(1)　Smartphone　addiction　has　a　positive　impact　related　to　mobile　user　behavior　when　driving,　(2)　Drivers　with　high　smartphone　addiction　are　more　likely　to　have　mobile　phone　use　related　to　cognitive　distraction　while　driving,　(3)　Visual　distraction　has　a　more　significant　impact　on　task　conversion　of　drivers　with　low　smartphone　addiction,　while　cognitive　distraction　has　a　more　significant　impact　on　task　conversion　of　drivers　with　high　smartphone　addiction,　and　(4)　SAS-C　total　score　and　psychological　characteristics　can　predict　RT(Response　time)under　cognitive　subtask　conditions.　The　results　of　this　study　should　help　develop　programs　for　driver　training　and　education.　©　2022,　The　Author(s),　under　exclusive　license　to　Springer　Nature　Singapore　Pte　Ltd.