A taekwondo instructor has confessed to the triple murder of an entire family in Sydney’s west.

Kwang Kyung Yoo, 50, was charged in February 2024 with murdering his seven-year-old student and the boy’s parents, Min Cho, 41, and Steven Cho, 39.

Yoo pleaded guilty on Thursday to three counts of murder, prompting emotional scenes in court as the victims’ family broke down in tears.

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The North Kellyville man spoke only briefly via video link, responding “yes, sir” and bowing his head when the magistrate confirmed his guilty pleas.

The bodies of the boy and his mother were found inside a taekwondo studio in North Parramatta on February 20, 2024, about two hours after Steven Cho was found dead in a townhouse on Watkins Rd in Baulkham Hills.

Taekwondo instructor Kwang Kyung Yoo (left) has confessed to the triple murder of Steven and Min Cho and their young son (right). Credit: Supplied, 7NEWS

Police allege Yoo strangled the mother and son sometime between 5.30pm and 6.30pm on February 19, left their bodies at the studio, and then drove the woman’s BMW to the family home at Baulkham Hills.

There, he allegedly stabbed the father to death between 9pm and 10.59pm.

The following morning, Yoo presented at Westmead Hospital with serious but non-life-threatening slash wounds to his chest, arms and stomach.

He told police he had been attacked in a supermarket carpark on Church St in North Parramatta the night before, prompting hospital staff to alert authorities.

Yoo has remained in custody since his arrest.

Police allege Yoo strangled the seven-year-old boy and his mother, Min Cho, before fatally stabbing the father, Steven Cho. Credit: Supplied

Known to his students as Master Lion at Lion’s Taekwondo Martial Arts Academy, Yoo portrayed himself on social media as a gentle family man.

At the funeral, grieving relatives of the Cho family bid a heartbreaking farewell.

“My wife and I face a frightening and dark abyss,” Steven Cho’s father, Jong Yoon Cho, said.

“My son’s family left for a better place — heaven.”

The matter will now proceed to the Supreme Court for arraignment, where the guilty pleas will be formally entered again.

A sentencing date will then be set.