Merlyna

Main Cast

 * Jhazmyne Tobias as Merlyna Curtis (mermaid/human) - She's a teenager who's half human and half mermaid. She's the crown princess of Oceanalia and has orange and pink tail. She is a high school teenager who loves a good family and a strong princess of underwater kingdom.
 * Hiro Volante as Gabriel Guevara (human) - Merlyna's love interest
 * Diether Ocampo as Albert Curtis (human) - Merlyna's father, who was a human.
 * Coney Reyes as Marita Curtis (human) - Merlyna's grandmother
 * Freddie Webb as Allan Curtis (human) -  Merlyna's grandfather
 * Jennifer Sevilla as Maritoni Guevara (human) - Gabriel's mom.
 * Keempee de Leon as Allan Guevara (human) - Gabriel's dad.
 * Dimples Romana as Elisa Curtis aka Queen Elisa (mermaid/human) - Merlyna's mother, a mermaid with a blue and yellow tail. She's the Queen of Oceanalia. She is fair and brave woman. Her worst nightmare is when she does not have the ability to swim.
 * Alliah Michelle as the voice of Zumy (sea creatures) -, a pink, sparkly dolphin who is friends with Merlya.
 * Francyss Abuan as the voice of Sloutty (sea creatures) - a helpful sea lion who is friends with Merlyna. He belongs to Xyriel and Joanne.

Supporting Cast
Mermaids Sea creatures Villains
 * Zaijian Jaranilla as Joshua David - Gabriel's bestfriend.
 * Giann Solante as Tricia - one of Merlyna's classmates/bestfriends.
 * She is talented surfer who kicks it on the waves.
 * Mianne Fajardo as Anne - one of Merlyna's classmates/bestfriends. Despite being somewhat odd-mannered, she is regarded as an excellent surfer.
 * Sophia Margarette To as Chelsea - Merlyna's classmate/friend.
 * Ryan James Bacalla as Zanjay Magundayao - Gabriel's classmate/friend.
 * Fenech Veloso as Xyriel - Merlyna's bestfriend and super-stylish mermaid. She own a luxurious boutique under the sea where Merlyna is a mermaid. They own Sloutty, a sea lion pup. They own Sloutty, a sea lion pup. They help Merlyna fight the evil Melda. She has blonde hair with blue streaks.
 * Mary Jaydeeryn Elias as Joanna - Merlyna's bestfriend and super-stylish mermaid. She own a luxurious boutique under the sea where Merlyna is a mermaid. They own Sloutty, a sea lion pup. They own Sloutty, a sea lion pup. They help Merlyna fight the evil Melda. She has brown hair with purple streaks.
 * NJ Roben Asunto as the voice of Callie - a blue seahorse who wears a necklace.
 * Krista Ranillo as Melda - the primary antagonist, an evil mermaid with an orange tail. She is Elisa's evil younger sister and Merlyna's aunt, who wants to dethrone Elisa and force others to worship her. To this end, she uses a new spell that forces everyone's worst nightmares to come true. Her own worst nightmare is having legs.
 * Baron Geisler (voice)

Special Participation

 * Alessandra Sophia as young Merlyna (mermaid)