Finally, a copy of our earnings release and a recording of this call will be available on our website, www.joesjeans.com, and a telephone replay will be available for one week from today.
Now I'll turn the call over to Marc.
Marc B. Crossman
Thanks, Lori, and thanks to everyone for joining us today. I'll speak about the first quarter results, and then I'll turn the call over to Hamish for a discussion of our financials. Finally, we will end with a Q&A session.
In the first quarter, we generated net sales of $26 million, an increase of 23%. The increase in sales is indicative of 2 trends that we started seeing in the fourth quarter of fiscal 2011. First, our wholesale business has stabilized and even begun to show increases, with else being 19% increase from the prior year period. Second, our retail strategy continues to provide material diversification to our revenue base, representing 20% of our revenues for the quarter and increasing 40% over the prior year. During the quarter, our operating income increased by 244%, resulting in operating income of $1.8 million.
Our retail division sales increased by 40% to $5.2 million for the quarter. Sales growth was driven by a very healthy 22% same-store sales increase, plus the addition of 4 more stores. For the first quarter, both our full-priced business and our outlets had healthy same-store sales gains, with our full-priced same-store sales up over 70%. With the first half of our second quarter underway, we are continuing to see solid same-store sales growth at our stores. Our retail gross margins increased 70% from 68% in the prior year quarter, primarily due to the addition of 4 stores, which included one full-priced store. Our strong same-store sales gain, coupled with the increase in gross margins, led to a 5% operating income margin, a big improvement over our negative 3% operating income margin a year ago. Also, our store-level operating margins more than tripled from the year-ago margins.