Indonesian Siti Aisyah, 25, and Doan Thi Huong, 28, from Vietnam, made their first public appearance since their arrest in the days after the sensational February 13 killing of the North Korean leader's half brother.
If convicted of the murder at Kuala Lumpur's international airport they face death by hanging.
The pair arrived at the isolated courthouse outside the capital in a police van, part of a convoy of 20 vehicles escorted by police outriders.
The van and the entrance to the building were secured by more than 100 heavily armed police wearing balaclavas and wielding automatic weapons.
The women entered the building wearing t-shirts, surrounded by a scrum of reporters and police.
Police accuse the suspects of having wiped the VX nerve agent, developed for chemical warfare, into Kim's face.
They claim they thought they were taking part in a prank video, and Siti reportedly told an Indonesian diplomat she was paid just 400 ringgit ($90) for her role, adding she believed she was handling a liquid like "baby oil".
Before the women arrived, Siti's lawyer Gooi Soon Seng told reporters that charges were due to be read out but no plea would be taken, with the prosecution set to request the case be transferred to a higher court.
"It will take months before the trial proper can start," he added.
The spectacular killing sparked an international probe and lurid stories of Pyongyang's Cold War-style tradecraft.
Seoul says its isolated neighbour was behind the assassination, and claims the North's agents engaged two outsiders to carry out the murder.
North Korea has not acknowledged the identity of the dead man but has insisted Malaysia hand over the corpse, and says it does not accept the findings of an autopsy.