CEO Mike Ullman said the gains show the company's turnaround is on track. The last time that JCPenney showed positive quarterly same-store sales growth was in July 2011.
The company has been cutting prices aggressively to bring shoppers back since former CEO Ron Johnson was fired in April.
Johnson was highly criticized for alienating millions of customers by doing away with discounts and coupons.
The company recently announced plans to close 33 underperforming stores and lay off more than 2,000 workers.