The invention relates to a manufacturing method for ferrum-silicon-aluminum magnetic cores. The manufacturing method for the ferrum-silicon-aluminum magnetic cores includes that ferrum-silicon-aluminum magnetic powder is processed through acid and then dry-pressed, so that the power is easy to mold, product density is improved, and meanwhile, the power can achieve high magnetic conductivity after heat treatment. Compared with the prior art, the manufacturing method for the ferrum-silicon-aluminum magnetic cores has the advantages that by means of control of the appending proportion, intensity of pressure of molding, sintering temperature and the like in power allocation, the ferrum-silicon-aluminum magnetic cores with 147 (+/- 8%) of magnetic conductivity are manufactured, and the ferrum-silicon-aluminum magnetic cores are low in iron loss and good in composition performance; process sequences are simple; and raw and auxiliary materials are low in cost.