Complete Guide to the Music of Madonna, author Rikky Rooksby explained that the song was Madonna's best take on her original music style. Stephen Thomas Erlewine of AllMusic commented that "Who's That Girl" along with "Causing a Commotion" were not amongst Madonna's best singles. Similar thoughts were shared by Medium's Richard LaBeau. Biographer J. Randy Taraborrelli, in his book Madonna: An Intimate Biography called the song "quintessential Madonna music" and went on to describe it as "funky, sassy and melodic, with a Latin accent". Writing for Slant Magazine, Ed Gonzalez hailed it a "calorie-free palate cleanser after the delectable voluptuousness of 'La Isla Bonita' [...] the music is catchy without ever stepping outside any norm". Rolling Stone called it "a bright dance-popper that fared much better than the lackluster film it was tied to". Noah Robischon from Entertainment Weekly opined that with both the song and the movie, Madonna had pushed "synergy over the borderline". From the same magazine, Chuck Arnold wrote: "The most memorable thing about Madonna’s 1987 comedy is the chart-topping title tune of its soundtrack. While it’s not quite in the league of its obvious inspiration, 'La Isla Bonita', this tropical delight is pure enchantment". Online magazine Queerty called it "simple enough for [Madonna] to perform convincingly and catchy enough for fans to remember". Louis Virtel from The Backlot ranked it at number 61 on a list for "The 100 Greatest Madonna Songs", and called it "a sexy little tribute to those minxes you just can’t catch up with". Enio Chiola of PopMatters.com listed "Who's That Girl" as one of the top-fifteen singles of Madonna's career, stating that it is an "insta-party from the moment in begins". In August 2018, Billboard ranked it as the singer's 62nd greatest song; Andrew Unterberger opined that it "expanded on the Spanglish hook and Latin-flavored pop bounce of 'La Isla Bonita' with a similarly contagious chorus and sparkling production from Madonna and Patrick Leonard". Jude Rogers from The Guardian felt that "as Balearic moments go, 'La Isla Bonita' was better". Writing for Gay Star News, Joe Morgan said that it was "not the best time we saw her Spanish influence, but it certainly wasn’t the worst. Great fun song, but a bit forgettable". Matthew Jacobs from HuffPost, placed it at number 52 of his list "The Definitive Ranking Of Madonna Singles" and called it "Madonna’s least-remembered No. 1 hit". On 2019,