Carbon black/PVDF copolymer (CB/PVDF copolymer) nanofiber composite has been synthesized by electrospinning process. Nanostructure and surface property of CB/PVDF copolymer were studied by using Scanning Electron Microscopy (SEM), Fourier Transform Infrared Spectroscopy (FTIR), X-ray Diffraction (XRD) and water contact angle (WCA). Nanofiber composite has smooth surface morphology without bead on nanofiber string. Increase of CB content in nanofiber composite decreased diameter of nanofiber size. Range of average nanofiber diameter was from 405.2 and 421.3 nm where it depended on CB content in nanofiber composite. FTIR and XRD analysis showed that structure of PVDF copolymer in nanofiber composite had a dominant β phase crystal structure. The β phase was showed and confirmed by vibration band peak at 838.55 cm-1 of IR spectrum and 2θ = 20.44° of XRD. Presence of CB in nanofiber composite also influenced WCA and water spreading on nanofiber composite. WCA of pristine PVDF copolymer, CB/PVDF copolymer nanofiber with 1% CB, and CB/PVDF copolymer with 5% CB were 113.8, 105.2, 117.3°. From this result showed that nanostructure and surface characteristic can be adjusted and controlled by presence of CB in nanofiber composite. This result has potential application for air filtration to solve air pollution issued. Keywords: CB/PVDF copolymer nanofiber composite, carbon black, nanostructure, electrospinning, water contact angle of nanofiber composite Kulcsszavak: CB/PVDF kopolimer nanoszál kompozit, szén fekete, nanoszerkezet, elektroszálképzés, víz nedvesítési szöge nanoszál kompoziton ARDENISWAN He received his master degree in environmental engineering, Bandung Institute of Technology. His research interest is in the field of hazardous waste and environmental monitoring such as air and water pollution. The 11th International Conference on the Science of Hard Materials (ICSHM11) attempts to bring together scientists, technologists and manufacturers of Hard Materials. This broad but unique set of materials includes technically successful and continuously evolving subgroups such as cemented carbides, cermets, advanced ceramics, composites and super-hard materials. Through the years, synergy between science and technology has catalyzed achievement of superior quality and enhanced performance of components, tools and devices of hard materials by means of innovative microstructural design at different length-scales: bulk/film, monolithic/composite, functionally graded, surface modified, and micro/nano-structures. As a consequence, the range of applications for hard materials has been growing not only within consolidated sectors such as metalworking, mining, oil-and gas-drilling, construction, process and machine building industries, but also into high-tech and emerging technologies in the electronics, aeronautics and dental sectors, among others. As it has been the tradition in the previous ten conferences, the aim of ICSHM11 will be to provide an interdisciplinary forum for presentation, discussion and exchange of modeling,...