Hollie joined the Bluebirds in late 2021 from Cardiff City Ladies.
Smith has played in the heart of defence for most of her career to date, but filled in admirably at right-back during the second half of the 2021/22 campaign, playing a key part as the Bluebirds won the FAW Women's Cup.
She is a Wales U19 international.
Iain Darbyshire, Head of Women's & Girls' Football at Cardiff City Football Club: “Hollie was a great signing for us last season and put in some brilliant performances straight away. She slotted into the group really comfortably and is a strong defender, whose attitude was brilliant in having to fill in at right-back for us at times last year.”