A hydrogen storage electrode alloy Ml(0.7)Mg(1.2)Ni(2.8)Co(0.6) was obtained by inductive melting of La-rich mischmetal and some other alloy elements such as Mg, Ni and Co. XRD, SEM and EDX analyses indicated that the microstructure of the prepared alloy was composed of LaNi5 phase as matrix and La5Mg2Ni21 as secondary phase. The highest hydrogen absorption concentration is 1.58 wt% at 302 K through pressure-concentration-temperature (P-C-T) curves measurement. The discharge capacity reaches 380 mAh/g, which is 20% higher than that of traditional LaNi5 type alloys. However, the cycle stability needs to be improved further for commercialization. The formation of La5Mg2Ni21 secondary phase is the key factor for the high capacity of the alloy. (C) 2002 International Association for Hydrogen Energy. Published by Elsevier Science Ltd. All rights reserved.