The robberies, one in Parkchester and one in Eastchester, happened a little more than a week apart.
In both cases, a woman in the salon was hit with a gun then had her purse snatched.
The incidents happened on October 27 at Nails At Last on Castle Hill Avenue and on November 5 at Beauty and Nail Salon on Boston Road.
The suspect is described as a 23-year-old black male, approximately 5-foot to 5-foot-6 and weighing 120 to 150 pounds. He was last seen wearing a black jacket and carrying a knapsack.
Anyone with information is asked to call Crime Stoppers at (800) 577-TIPS (8477).