Amy Gerard, 28, was last seen in the early hours last Friday, outside the Molly Malone Irish bar in Puerto de la Cruz.
She works at the Loro Parque marine theme park on the outskirts of the resort.
A missing person appeal issued by Spanish police has been shared hundreds of times on social media after being tweeted by her sister Chloe, who lives in Sheffield.
Today she thanked everyone for sharing the appeal - but said there was no new information.
She tweeted: "We’re working closely with the local police who are doing everything they can to find Amy.
"We appreciate all the exposure on Amy’s disappearance and continue to urge anyone to come forward if you think you saw her."
The Foreign and Commonwealth Office said it was assisting the family of a British woman in Tenerife.