Abstract. High temperature shape memory alloys have received a large interest for many years but none of the systems studied so far has led to industrial applications. Those alloys are expected to develop an actuating role in high temperature environment as for example aircraft turbines. Lots of criteria are required in order to substitute or optimize heavy existing actuators. Here are presented a few results obtained with the system hafnium-palladium, not so documented for the moment, that develops a martensitic transformation at around 773 K. According to the characteristics of very well-known alloys such as NiTi, some compositions around the equiatomic are explored. The main objective of our work is to know the influence of a stoechiometry gap on the microstructure of the alloys and the martensitic transformation.