The 32-year-old 'Perfume' hitmaker, who has been dating David Lucado since last March, fell in love with the teacup Yorkie named Micro Diamond at Star Yorkie in the San Fernando Valley area of Los Angeles, reported Radar online.
"Britney and David were friendly. She was in a great mood and seemed happy playing with the puppies," the pet shop's owner said.
"They left empty-handed, but I wouldn't be surprised if they come back for Diamond," he added.
Spears, who has sons, Sean, eight, and Jayden, seven, with her ex-husband Kevin Federline, is a well-known animal lover and has adopted a Yorkie and a Maltese from the same pet shop in the past.