Nude photos of the 19-year-old ex-fiancé of Palin's daughter, Bristol, were a huge hit last fall on the magazine's website.
The young couple broke up in late 2008 after the birth of their son, Tripp.
A Playgirl spokesman Daniel Nardicio said that the spread includes an interview with Johnston, who talks about his strained relationship with the Palins.
The publisher anticipates major demand for the photos, also from the last shoot, when they appear in the newly revived print version. The magazine will hit newsstands on 22 February.