In this research, path planning and motion analysis of a palm climbing robot is studied. To this goal, a suitable mechanism is chosen. Then geometrical specification of the mechanism is described and in the following, inverse and forward kinematic of the robot is analyzed. Next, the jacobian of the robot is calculated and an algorithm for the singularity avoidance is applied. To generalize the problem, it is assumed that the robot has the ability to climb up any unknown trajectory in the space. To compute desired position and orientation of the end-effector at any time, path planning becomes necessary for the robot. Path planning is the computation of desired motion profiles for the actuation system of automatic machines and includes two sections: the geometric path approximation and motion law. In this study, two different algorithms for the first section are presented. The so called point-to-point algorithm approximates the path with a limited number of points on the path. The so called tangential algorithm approximates the path by estimation of the tangent vector to the path at any moment. The second section is the motion law. Motion law is a parametric function of time so that the given constraints on velocities, accelerations, and so on, are satisfied. The motion law for this robot should be such that the speed of the actuators at the beginning and at the end of motion increase or decrease gradually. To implement the path planning algorithms on the robot, some environmental information is required. To extract this information, several ultrasonic sensors may be used. To avoid exceeding the length of the legs to their allowable values, suitable equations are presented. After that, a solution is offered to prevent the robot and tree collision during rotation of the robot around its axis. For controlling the robot so that the end-effector follows the desired trajectory, a proportional controller is presented. Since determining desired forces in the actuators is needed, the inverse dynamic analysis on the robot is performed. To plan the path, both of the path planning algorithms are simulated. The results show that the tangential algorithm, approximates the path better than the point to point algorithm. Finally the robot is designed and illustrated in CAD model. Keywords: Climbing robot, Unknown trajectory, Kinematic analysis, Path planning, inverse dynamic, Simulation