The invention discloses a system for generating a soot blowing steam source through steam ejection flow technology. The source of the soot blowing steam source comprises the two branches of a high-pressure low-temperature steam source and a low-pressure high-temperature steam source. Through steam ejection technology, low-pressure steam is ejected through high-pressure steam, and control over the flow proportion of the two streams of steam and the pressure and temperature of mixed steam is achieved. The mixed steam can also be further adjusted in a mixed steam pipeline through a mixed steam pressure adjusting valve to obtain the parameters meeting the requirements of steam soot blowing of a soot blower finally. The system has the characteristics that the steam source composition is flexible, the system is simple, and the soot blowing adaptability is high. The system is suitable for design and usage of a soot blowing steam source of a soot blowing system of a newly built power station boiler and also suitable for transformation of a soot blowing steam source of an in-service unit. The energy consumption of boiler steam soot blowing can be lowered significantly, deep energy saving of a power station boiler is helped to be achieved, the safety of boiler steam soot blowing is also improved, and soot blowing repair and maintenance workload and cost are reduced.