Spill fires caused by oil leakage from tankers may pose a threat to the liquid transportation safety. In this paper, a series of large-scale gasoline continuous spill fire experiments were conducted on a water surface. The spread area, flame height, burning rate and the temperatures in the water layer were measured for different fuel discharge rates and ignition delays. The findings showed that the spread process can be well predicted by an existing spread model without ignition. For ignited conditions, four burning phases were identified, namely (i) spread burning phase, (ii) shrinking burning phase, (iii) quasi-steady burning phase, and (iv) extinguishment phase. The burning rate at the quasi-steady phase was found to be approximately 45–62 % that of pool fires with the same burning area. Subsequently, a model was developed for predicting the quasi-steady burning rate of spill fires. The flame height at the quasi-steady burning phase was also analyzed and correlated with the fuel discharge rate. Finally, a model was proposed to predict the maximum burning area at the spread burning phase and validated against the experimental data. The present results are of practical importance in understanding the spread and burning characteristics of continuous spill fires and the associated risk assessment.