Transurethral double J (DJ) stent placement is a standard method for drainage during ureteral obstruction caused by a ureteral stone and for the management of complications after transurethral ureterolithotripsy (TUL). This is a safe and minimally invasive technique; however, severe cases of DJ stent migration have been reported, although rarely. Herein, we report the CASE of a 48-year-old man with DJ stent migration as renal penetration, which arose as a complication after an unsuccessful TUL. As transurethral DJ stent placement is one of the basic techniques performed by urologists, possible rare complications of the placement should be taken into consideration.