Williams is slated to join her sister again on the Washington Kastles team. The WTT website has Serena playing July 7 at home against Boston and July 9 at Sacramento.
WTT spokeswoman Rosie Crews said Thursday that "Serena talked about being excited about coming back to play World TeamTennis in July" during a recent benefit in D.C.
The 13-time Grand Slam singles champion has been sidelined since Wimbledon because of foot surgery and blood clots in her lung.
Tennis Channel will air live matches on Wednesdays in July.
The nine-team coed league, co-founded by Billie Jean King, opens July 4. The final is July 24 in Charleston, S.C.