El pecado de Oyuki (English title: Oyuki's Sin alt. The Sin of Oyuki, in Japanese Oyuki (の罪)) is a Mexican telenovela produced by Lucy Orozco for Televisa in 1988. The series was based on an original comic book of the same name by Yolanda Vargas Dulché, who also adapted the screenplay for television. The comic tells the story of Oyuki, a young Japanese woman unfairly exploited by her evil brother. Her tragedy is intensified by falling in love with the son of the English ambassador in Japan, which triggers a series of obstacles in her path generated by the cultural shock.

The story was adapted for the telenovela format by Vargas Dulché and produced by Lucy Orozco for Televisa.

The world premiere of the telenovela was in the United States in 1987 through Univision with one hour episodes during primetime. It was not until February 1988 when it premiered in Mexico also in primetime through El Canal de las Estrellas.

The main characters of the story were played by Mexican actress Ana Martín and Argentine actor Boy Olmi.

The telenovela became one of the biggest successful projects by Mexican television at that time, nationwide and also internationally.