The ignition process of boron particles in relatively static atmosphere was studied systemically. In view of the gas flow around the boron particle, the heat and mass transfer process between the boron particle and the surroundings, a one dimensional ignition model of boron particles was proposed. The changing regularities of important parameters of the gas and the particle in the two typical cases, namely, the successful ignition case and the degenerate ignition case were studied. And the mechanisms for them were analyzed in detail. The result shows that Stefan flow in both typical cases will undergo changing flow direction. Stefan flow undergoes flowing to the particle surface from the gas, and then it flows to the gas from the particle surface. Study of ignition process of boron particles in the paper shows that ignition time decrease with consideration of Stefan flow at the particle surface. And the effect increases with the ambient pressure.