We investigated the seawater methanol abundance in the northwest Pacific Ocean (NWPO) area. Seawater samples were collected during May-June 2021 aboard the R/V “Dongfanghong 3” in the northwest Pacific Ocean. Seawater was sampled using a Seabird 911 CTD-Niskin rosette system equipped with conductivity, temperature and depth sensors. Methanol samples were collected directly without filters and then stored at -80℃ for laboratory analysis. Methanol concentrations were determined by a modified commercial purge and trap system combined with Agilent GC-8890 gas chromatograph with a flame ionization detector. This dataset includes two over 5000m depth profiles of methanol.