There were doubts over Gu Juan's future when her mentor and national coach, Luan Ching, was removed by the Singapore Badminton Association (SBA) in January.
Yesterday, the SBA confirmed that the shuttler, who turns 24 later this month, has quit.
The announcement came as the association announced the squads for the Thomas Cup and Uber Cup in India later this month.
The statement said that Gu Juan (right) had tendered her resignation on April 30, citing nagging injuries and a desire to look after her aged parents as reasons for her departure.
She also expressed her reluctance to train under the current system, which is overseen by national head coach Liu Qingdong, claiming "they are unable to bring me to the next level".
SBA chief executive officer Ronnie Lim said: "Gu Juan had expressed her desire to resign earlier this year and we have tried to encourage her to stay and give the new coaching system a chance, but she was reluctant.
"She was also carrying injuries and skipped several training sessions.
"Hence, we thought it was better for all parties to let her go."
While she reached a career-high world-ranking of 15 under Luan Ching, Gu Juan never won a senior title in her career.