Fe-based bulk metallic glasses (BMGs) are attractive for the engineering applications as functional materials because of their excellent soft magnetic properties, very high strength, viscous flow workability in the supercooled liquid region (ΔTx = Tx-Tg, Tg: glass transition temperature; Tg: crystallization temperature), and low material cost . Recently, the thermoplastic processing has been expected to make highly functional micro-/nano-parts and electromechanical devices on the soft magnetic Fe-based BMGs by suing the viscous flow workability [1,2]. The suitable BMGs for thermoplastic processes have to possess simultaneously low Tg, large ΔTx, and high glass-forming ability (GFA). From a processing point of view, it is desirable to possess a large ΔTx which gives access to a low forming viscosity, which in turn facilitates thermoplastic forming. A low Tg implies a low processing temperature since it facilitates processing . In addition, a low Tg can prevent the reaction of the metallic glasses with mold materials. However, most of the Fe-based BMGs with good soft magnetic properties exhibited high Tg, small ΔTx, low GFA or high viscosity in the supercooled liquid state, which hinder their thermoplastic formability. In this work, with the aim of developing new ferromagnetic Fe-based BMGs with low Tg, large ΔTx and high GFA for the thermoplastic processing, we investigated the effect of alloying additions on the thermal stability, GFA, magnetic properties of the Fe-P-C-B metallic glasses with low Tg.