The 48-year-old suspect is accused of stalking Cho Hye-yeon, 35, for a year until last April and leaving messages and profanity on the outer wall of her academy teaching Go, called "baduk" in Korean.
"The nature of the suspect's crime is very bad to the extent that the victim hired a private bodyguard due to trauma and anxiety that she wasn't being properly protected under the country's criminal justice system," judge Heo Gyeong-ho of the Seoul Northern District Court said in handing down the sentence.
"However, (the court) took into consideration the fact that (the accused) has a record of being treated for schizophrenia and that some of his offenses were accidental," he added.
Prosecutors also indicted the man on other charges, including obstruction of business and blackmail. The court convicted him of most of the charges, citing the credibility of the victim's testimony and the same handwriting used to write on the wall.
The suspect pleaded guilty to charges of damaging property, by writing "I miss you" on the academy wall last October, but denied all other charges.
The man allegedly made a scene when he visited the academy and wrote words such as "I love you" and "dirty woman" on the wall.
On three consecutive days in April, he allegedly came to the academy and yelled that he and Cho were to be married.
The man also left threatening comments on online news articles on Cho's victory in a Go competition, according to the court.
The case drew public attention after Cho wrote a petition on Cheong Wa Dae's website in late April, complaining of her mental suffering and lax punishment for stalking.
Stalking is considered a misdemeanor in South Korea and is punished under the minor offenses act. (Yonhap)