The report said 2,298 children and 1,536 women were among those killed.
A total of 4,148 civilians, including 754 children and 591 women were killed by torture and attacks carried out by the Assad regime last year, it said.
Also, 316 civilians, including 58 children and 54 women were killed by the PKK/PYD terror group in Syria while another 1,421 civilians, including 281 children and 148 women were killed by Daesh terrorists.
Attacks carried out by Russian forces killed 1,436 civilians, including 439 children and 284 women while 1,759 civilians were killed in attacks of the U.S.-led coalition.
In the clashes between military dissidents and anti-regime groups, 211 civilians including 47 children and 30 women were killed.
Separately, 913 civilians were killed by unknown sides.
According to the report, 2,019 civilians in the suburbs of Damascus, 1,512 civilians in Raqqa, 1,352 in Aleppo, as well as 1,324 others Deir ez-Zour and 1,256 civilians in Idlib were killed.
Also, 882 civilians in Daraa, 852 in Hama and 781 in Homs as well as 198 in Hasakah and 28 other civilians in Quneitra province were killed.
The report said 211 civilians in 2017 were killed after regime's tortures.
It also urged Russia as the guarantor state for Assad to demand the regime to abide by the terms of agreement on de-escalation zones.