Axion originated from a solution to the strong-CP problem[1, 2]. During the past decade, axion and other light pseudoscalar bosons (< 1 eV/c^2) which are collectively referred to as axion-like particles or ALPs have become well-motivated dark matter (DM) candidates. The cosmic axion spin precession experiment (CASPEr)[3] aims at probing axion and ALPs with nuclear magnetic resonance (NMR) technique. CASPEr-Gradient in Mainz searches for the coupling of nuclear spins to the gradient of the ALP field[4]. The experimental apparatus was designed to scan ALP Compton frequency from 100 Hz to 600 MHz, corresponding to ALP mass range of approximately 10^-13 to 10^-6 eV. The detection system has been commissioned for this research. We performed a 10-hr measurement with thermally-polarized liquid methanol sample with a 25 ppm homogeneity at the 317 G leading field, which corresponds to searching for an ALP field at 1.349533 MHz with 33 Hz bandwidth. Noise of the setup and ALP coupling constant exclusion have been analyzed for the measurement.