With the high-precision nano-vibrator as the vibration target to be measured, this paper studied the swept-source optical coherence tomography (SS-OCT) method based on ultra-small gradient index (GRIN) fiber probes for vibration measurement. The working performance of the integrated SS-OCT based on ultra-small GRIN fiber probe was assessed. In theory, the system can measure the maximum peak-to-peak value of vibration up to 12.5 mm and the maximum frequency up to 25 kHz. The corresponding vibration measurement system was developed and the tests and analysis of micro-vibrations were performed. The results show that, with the peak-to-peak value range of 1 nm--5 μm for the nano-vibrator and the frequency range of 1--200 Hz, the integrated SS-OCT vibration measurement system can detect micro-vibrations with a frequency of 1 Hz and a peak-to-peak value of 6 nm or above. For a single-frequency sinusoidal vibration signal with an amplitude of 25 nm and a frequency of 10 Hz, the system has a repeatability-test standard deviation of 0.003. It shows that the integrated SS-OCT system based on the ultra-small GRIN fiber probe has the feasibility of measuring micro-vibrations, which provides an experimental basis for further research on its application in precise measurement fields such as micro-vibrations and micro-displacements.