To reduce the soot emissions of diesel engines, 20% polyoxymethylene dimethyl ethers (PODE) or gasoline by volume is blended in diesel (D80P20 and D80G20) and experimental studies have been carried out to compare the combustion and emission of blend fuels with diesel. Compared to diesel, D80P20 and D80G20 shorten the combustion duration, improve the brake thermal efficiency (BTE), increase the NOx emission and decrease the soot emissions and the number concentrations (NCs) of ultrafine particles (UFPs) in most cases. Strong premixed combustion and enhancement of air entrainment contribute to the highest BTE and NOx emissions of D80G20 at low and partial loads. Strong diffusion combustion contributes to the highest BTE and NOx emissions and the lowest soot and UFPs emissions of D80P20 at medium and high loads. To balance the NOx and soot emissions, PODE and gasoline are simultaneously added in diesel by 10% volume. BTE and NOx emission of D80G10P10 always rank the second. It has the lowest soot and UFPs emissions from 0.16 MPa to 0.48 MPa BMEP among the four fuels. Compared to diesel with original injection timing, suitable delay for D80G10P10 can simultaneously reduce the NOx, soot and UFPs emissions in the whole load range. (C) 2019 Elsevier Ltd. All rights reserved.