Prosecutors say the murders took place on 29 and 30 June 2008 in a remote forested area close to Yaroslavl with two victims killed per night.
The self-styled devil worshippers, which included a young teenage girl, lured three girls and a boy aged from 15 to 17 to the spot by plying them with alcohol and inviting them to sit round a bonfire.
They then killed them in a sacrificial ceremony, stabbing them 666 times each in homage to the so-called Number of the Beast.
Prosecutors say the young killers then dismembered their victims' bodies and cooked certain body parts such as the hearts and the tongues before consuming them.
They buried the rest of the remains in a giant pit which they marked with an inverted cross topped with a dead cat. Investigators say the sect was formed in 2006 and gleaned its knowledge of Satanism from the Internet, initially killing cats and dogs before graduating to homicide.
The case has shocked inhabitants of the historic city of Yaroslavl some 150 miles north-east of Moscow which is one of Russia's 'Golden Ring' tourist destinations and better known for its beautiful churches and monasteries than grisly ritual killings.
The defendants' young age - four of the accused were under eighteen at the time of the murders - and the sheer cruelty of their crimes combined with the fact that none of them came from poor families has left many locals struggling to understand their motives.
The case is being held behind closed doors but local media say all seven defendants admit their guilt. They are officially charged with murder, theft and the desecration of human remains.
They would typically be jailed for life but the fact that four of the defendants were minors at the time means they are likely to get off more lightly.