Pistorius, who became the first double-amputee runner to compete on the track at the Olympics at last year's London Games, is accused of intentionally killing model Reeva Steenkamp. Pistorius says he mistook Steenkamp for an intruder and that the shooting was accidental.
"We believe Oscar Pistorius should be afforded due process and we will continue to monitor the situation closely," Nike said in a brief statement posted on its website Wednesday.
On Monday, eyewear maker Oakley Inc. suspended its contract with Pistorius.
Nike dropped Lance Armstrong in October, citing insurmountable evidence that he participated in doping and misled the company about those activities for more than a decade. But the Beaverton, Ore.-based company stood by Tiger Woods after he acknowledged infidelities and went to rehab for sex addiction.
Pistorius was born without fibula bones due to a congenital defect, and had his legs amputated at 11 months. He runs on carbon-fiber blades and was originally banned from competing against able-bodied peers because many argued that his blades gave him an unfair advantage.
In 2008, however, the Court of Arbitration for Sport cleared him to compete against the fastest in the world.
Pistorius is a multiple Paralympic
He won a silver medal with his country's 4x400 relay team at the 2011 world championships in Daegu, South Korea.