This archive includes two-dimensional (2D) wide-angle reflection/refraction seismic data (OBS2019ZX1) in the Southern South China Sea margin. Dataset was collected during July 2019, using R/V “Shiyan 2” that belongs to the South China Sea Institute of Oceanology, Chinese Academy of Sciences. The objective is to investigate the deep crustal structure and to reveal the rift-to-drift process in the southern South China Sea margin. Twenty-seven 4-component short-period OBSs, each comprising one hydrophone and a 3-component geophone, were deployed along the 315-km-long profile in 10 km intervals. The sample intervals were 4 ms, 10 ms, and 20 ms for different instruments. The seismic source consisted of an array of four BOLT air-guns with a total volume of 6,000 cubic inches, towed behind the vessel at a depth of 10 m. A total of 1,601 shots were fired at a pressure of 12.5-13.5 MPa with a shooting interval of 90 s, giving an average seismic trace spacing of ~220 m. Four instruments (OBS08, OBS09, OBS12, and OBS14) were not retrieved from the seafloor, and one instrument (OBS16) did not record usable data. Twenty-two OBSs were finally recovered with effective recording data. The format of seismic data in this repository is SEGY recorded by the OBS vertical or hydrophone component. Meanwhile, the location file of OBS stations and the navigation file of shots have also been submitted in this repository.