Abstract: This application relates to a robot arm structure and a manipulator of a surgical robot including the robot arm structure. The robot anti structure includes a first robot arm unit and a second robot arm unit. The first robot arm unit includes a plurality of first link arms, a first joint unit mounted on one of the first link arms and rotating the one of the first link arms about a first axis and a second joint unit installed on at least one of the plurality of first link arms to adjust a length of the at least one link arm. The second robot arm unit includes a second link arm connected to one of the first link arms and a third joint unit using a lengthwise direction of the second link arm as a first rotary shaft and rotating the second link arm.