Wide Distillation Fuel (WDF) refers to the fuels with a distillation range from initial boiling point (IBP) of gasoline to final boiling point (FBP) of diesel. In this paper, the WDF was prepared by blending diesel fuel and different gasoline fuels with various RONs (90#, 97# and 100#). Experiments were conducted on a direct injection diesel engine with these fuels to investigate the sensitivity of gasoline RON on combustion and emission characteristics in premixed LTC mode from medium load (6 bar IMEP) to high load (10 bar IMEP). The results indicate that WDF90 has slightly higher combustion efficiency at medium load with a slight increase in NOx emissions. At high load, no significant difference in combustion and emission characteristics was observed WDFs with different RONs from 90# to 100#. All of the three WDFs can significantly reduce soot emissions at both medium load and high load in LTC combustion compared with diesel fuel. Premixed low-temperature combustion of WDF is a promising approach to increase gasoline thermal efficiency compared to SI mode, whereas thermal efficiency is insensitive to gasoline RONs. (C) 2014 Elsevier Ltd. All rights reserved.