In 2013, Son started her season competing at the 2013 Moscow Grand Prix where she won bronze in clubs, she competed at the 2013 Lisboa World Cup where she finished 9th in all-around and won bronze in ribbon. On 30 April 2013, Son got a silver medal in the ribbon finals at the 2013 Pesaro World Cup, it was the first time a Korean athlete won a silver medal at any discipline of a rhythmic gymnastic World Cup. Son finished 4th in all-around at the 2013 Sofia World Cup and shared the bronze medal in hoop with Ukrainian Ganna Rizatdinova. Son then competed at the 2013 Minsk World Cup where she finished 4th in all-around, at the event finals, she took the silver medals in hoop and in clubs who was tied with Russian rising star Yana Kudryavtseva, she finished 4th in ribbon and 7th in ball. Son competed at the 2013 Asian Championships in Tashkent, Uzbekistan where she became the first Korean rhythmic gymnast to win gold in the all-around, she also helped Team Korea win the silver medal. At the finals, Son won gold in hoop and clubs, she won silver in ribbon behind China's Deng Senyue and finished 4th in ball. She competed at the 2013 Summer Universiade where she finished 6th in all-around, she qualified to 3 event finals where she won silver in ball, placed 5th in clubs and 7th in ribbon. At the 2013 World Cup series in St.Petersburg, Russia, Son finished 4th in all-around and in the event finals won silver in hoop, bronze in ribbon, placed 4th in clubs and ball. At the 2013 World Championships in Kiev, Ukraine, Son qualified to 3 event finals where she finished 7th in hoop, ball and 6th in clubs behind Deng Senyue. She finished 5th in the All-around at the 2013 World Championships again behind Chinese rival Deng Senyue who finished 4th.