A ten-page academic paper from Japan about fundamental data for the ignition and combustion of gas to liquid fuels, synthetic fuels planned to replace diesel fuel. Gas-to-liquid (GTL) fuel exhibits potential as a clean alternative diesel fuel, suitable for addressing problems of energy security and environmental pollution. The main objective of this research was to provide fundamental data for the ignition and combustion of GTL fuels. Experiments were conducted in a constant volume combustion vessel to investigate the effects of ambient temperature on ignition delay and combustion characteristics for various ambient pressures. Three kinds of GTL fuels with different distillation properties and their blends in gas-oil (conventional diesel fuel) were tested. The experimental results showed that all tested fuels exhibited similar ignition-delay trends: ignition delay increased as ambient temperature and ambient pressure decreased. The variation of ignition-delay values was small at temperatures higher than 700 K but large at temperatures less than 700 K. In addition, the results showed that the ignition-delay trends of GTL fuels depended significantly on distillation properties.GTL fuels with high cetane number corresponded to shorter ignition delay and smoother heat-release rate than those for gas-oil at the same temperature and pressure. Particularly, their good ignitability at low temperature might make it feasible to premixed-charge compression-ignition (PCCI) operations. In addition, the shadowgraph images showed that GTL fuels evaporated and mixed with the hot air quicker than gas-oil. Moreover, the blend GTL fuel helped improve ignition and combustion compared to gas-oil. The obtained results contribute to find the optimal condition of design and operation in diesel engines fuelled by GTL fuels.