The spread of burning fuel spilled from tanks or pipes during oil storage and transportation industries may threat other facilities nearby and trigger further accidents. In this paper, the effect of substrate slope on the continuously released liquid fuel spill fire was experimentally investigated, in a one-dimensional channel with different discharge rates and substrate slope angles. The time-varying burning area was recorded and analyzed, with 5 typical phases. It is observed that the maximum burning area increases largely with the increasing slope angle, while the steady burning area increases only a little. The steady burning rate, which equals the ratio of the discharge flow rate to the steady burning area, decreases with the increasing slope angle. It is proved that the burning rate for liquid fuel spill fire is much lower than that of pool fire with the same dimensions. The facilities and data presented in this work may provide a basis for the future modeling study of the liquid fuel spill fire on inclined surface. (C) 2017 Elsevier Ltd. All rights reserved.