One Russian prosecutor, two defense attaches, security officials, autopsy experts and officials from the country’s Ministry of Emergency Situations have examined the crime scene where Karlov was gunned down.
Turkish officials cooperated with the Russian delegates.
Some Russian officials examined Karlov's remains and those of the gunman, Mevlut Mert Altintas, at the Institution of Forensic Medicine in the Turkish capital.
Andrey Karlov died after being shot multiple times at an art exhibition in Ankara on Monday evening.
Karlov was delivering a speech when the assailant, 22-year-old policeman Altintas, opened fire on him.
The envoy's autopsy has been completed and his remains have been sent to Ankara’s Esenboga International Airport for a state ceremony before repatriation to Russia.
Deputy Prime Minister Tugrul Turkes, Interior Minister Suleyman Soylu and Justice Minister Bekir Bozdag attended the airport ceremony.
Karlov's family also flew to Moscow.
The delegation has visited the security headquarters in Ankara as well. The delegation met with Chief of Police Mahmut Karaaslan, who leads the investigation.
Turkish Foreign Minister Mevlut Cavusoglu on Tuesday said Ankara’s Karyagdi Street, where the Russian embassy is located, will be renamed Karlov Street in memory of the slain diplomat.
Another announcement came from the Municipality of Cankaya district where the art gallery in which Karlov was murdered is located. In a written statement, the municipality said the Contemporary Art Gallery -- where the murder happened -- will be renamed after Andrey Karlov.
Security has been tightened at Turkey's diplomatic missions in Russia following Monday’s shock assassination, according to the Russian Interior Ministry.
"Police stepped up security at Turkey’s diplomatic missions in the Russian Federation," ministry spokeswoman Irina Volk was quoted as saying by the official TASS news agency.
Volk said Turkey’s embassy in Moscow and consulates in Russian cities were now under "round-the-clock" protection.
The total number of arrests related to the assailant Altintas increased to 12 later Tuesday.
Early on Tuesday, six relatives and one roommate of the assassin were arrested by Turkish police. Hasan F., uncle of slain assassin Altintas, was released earlier Tuesday under judicial restrictions.
The uncle was a former senior executive at a Fetullah Terrorist Organization-linked private school shut down in an investigation following the July 15 defeated coup, which was blamed on the group.
Later, another suspect, Süleyman E., who is claimed to have led FETO network at the Izmir-based Rustu Unsal Police Academy from where Altintas graduated, was detained. Five other suspects related to Altintas were also detained, including 4 police officers hired in the same term as Altintas.