While in college at St. Paul, she played the lead role in One Legendary Evening and appeared in Show Boat as Magnolia followed by her performance as Nancy in the Philippine presentation of Oliver!.

The album featured Celeste's heartwarming Filipino renditions of Minnie Ripperton's Lovin' You, Diana Ross' Theme from Mahogany, and The Lady Is A Tramp.

She sang the part of the First Woman in the play "Tales of the Manuvu" (1977) produced by the CCP Dance Company, where she shared the stage with Hajji Alejandro.

(1988) for the Cultural Center of the Philippines' Tanghalang Pilipino, and the portrayals of Babae in North Diversion Road (1988), Caridad in the zarzuela Paglipas ng Dilim (1991), and Candida in Larawan (1992).

(1996), Larawan, the Musical (1997), Fire Water Woman (1999), and Saranggola ni Pepe (2008) [5] Along with theater icon Zeneida Amador, she was awarded as the first recipient of the "Natatanging Gawad Buhay!"

Legaspi, being the founding president of the Organisasyon ng Pilipinong Mang-aawit and Philstage, was key in establishing the Philippines' sole alliance of professional performing arts companies and organizations.

She also sang the main theme song of Kahit ang Mundo'y Magunaw (1975), a Manuel Cinco film starring Pilar Pilapil and Christopher de Leon.

In 2023, Legaspi played the role of a Filipino-Chinese businesswoman and Rowell Santiago's aunt in the ABS-CBN romantic drama series Can't Buy Me Love.

Her album Ako at si Celeste under Blackgold Records was awarded gold, and produced hit singles "Saranggola ni Pepe", "Tuliro", and "Gaano Ko Ikaw Kamahal?".

Celeste Legaspi claims she is greatly influenced by Barbra Streisand, Liza Minnelli, Lena Horne, and Ella Fitzgerald.