Flexibility of links and joints affects dynamic behavior of manipulators. In this work, the vibration characteristics of a one-link carbon-fiber box manipulator with a rectangular cross-section and a [0/90/0/90] lay-up are studied to examine the effects of the link and joint flexibility. The theoretical results supported with experimental studies are presented to realize the mentioned examinations. An experimental system, which consists of a composite box manipulator driven by a geared servo motor and a wireless measurement system, is introduced. Some parameters of the driver are manually set in the experiments. Vibration tests of the composite manipulator are realized for the stationary and nonstationary cases. Experimental vibration responses are both evaluated for auto and manual tune modes of the servo driver. Theoretical results obtained via the finite element vibration analysis compared with the experimental results. The changes of the natural frequencies and damping properties are presented for the stationary and nonstationary cases. The experimental vibration responses of the composite box manipulator with various payloads match well with the theoretical ones by tuning servo motor parameters manually.