The present invention relates to a flying object having small bottom blades, which is one type of unmanned rotor craft. A conventional bottom blade type flying object needs an apparatus having a complex configuration constituted by the combination of various components, such as servo, control plate, hinge, and so forth to control the rotor pitch at every instant and operate a control blade for flight control. However, the present invention provides a bottom-adjustable propeller-type flying object, wherein a circular frame with a fixing plate and a protective plate mounted thereto is installed at a lower part of an axis of a power propeller mounted to the center axis, and a control motor having a control propeller installed thereto is mounted to the protective plate. Accordingly, the flying object performs upward and downward flights using wind force generated by rotation of the power propeller, and performs hovering, and leftward, rightward, forward and rearward flights using wind force generated by rotation of the control propellers that are installed on two control motors. Further, components are arranged in such a manner as to locate a weight center of the flying object near the center axis.