The KwaZulu-Natal are new head coach Sinethemba Badela first signings of the January transfer window, with the former Chippa United boss having replaced Gavin Hunt in December.
Maarman (26) is a former Chippa United player, who has also turned out for Orlando Pirates and Cape Town All Stars, while Mahlangu joined Babina Noko from TS Galaxy.
Both players have struggled for game time under Eric Tinkler at Sekhukhune this season with Maarman playing five times while Mahlangu turned out just once.
A Durban City statement read: "New signings confirmed.
"Durban City FC welcomes Ronaldo Maarman and Siphiwe Mahlangu on loan from Sekhukhune United FC.
“Two experienced wingers. One ambition.”
Orlando Pirates midfielder Thalente Mbatha says his side are geared up for all three points in their first Betway Premiership clash since before the AFCON break away to Sekhukhune United on Saturday.
Gavin Hunt marked the start of his tenure at Stellenbosch FC with a narrow but valuable victory as his side edged Sekhukhune United 1-0 in a Betway Premiership clash at the New Peter Mokaba Stadium on Tuesday night.
Gavin Hunt will oversee his first match as Stellenbosch's FC new coach when they meet Sekhukhune United at the Peter Mokaba Stadium on Tuesday as Betway Premiership action resumes.
Rivaldo Coetzee is currently training with Sekhukhune United in a bid work his way back to fitness and win a contract, explains agent Mike Makaab.
