A surgical robots tool arms assembly comprises three movable tool arms mounted on a base provided for detachable fixing thereof on a support structure of a surgical robot. The first tool arm is centrally mounted on the base and has a first guide rail with at least one arch-shaped guide groove and in said guide groove slides a second guide rail also having at least one arch-shaped guide groove in which slides a third guide rail. The third guide rail is fixed to a base for securing a surgical instrument. Each of the two remaining tool arms is situated on the opposite sides of the first tool arm and connected to the base with a first platform rotatably mounted on the base. Each of the two tool arms comprises a slidably and rotatably mounted to the first platform guide rail with a slidably and rotatably mounted thereon second platform. On the second platform there is an immovably mounted first motor and to a shaft thereof is mounted a first pivot bracket on a second end thereof there is an immovably mounted second motor and to the shaft of the second motor there is mounted a second pivot bracket provided for mounting thereon further surgical instrument.