[[abstract]]The crystalline structure and magnetism of Co/W(111) and Co/faceted Pd/Wf112g surface are studied with low energy electron di raction (LEED), Auger electron spectroscopy (AES), temperature programmed thermal desorption (TPD) and magneto-optical Kerr e ect (MOKE). We nd that Co/W(111) has revealed in-plane ferromagnetic ordered for room temperature growth mode and both of in-plane and perpen- dicular magnetism for low temperature growth mode. Co undergo well epitaxial on W(111) because of the small lattice mismatch in a speci c orientaion. Co/faceted Pd/Wf112g reveals two-step hysteresis loops and we infer that alloys are formed. There is 40 Oe reduction in the magnetic coercivity of Co/faceted Pd/Wf112g when 1.8 langmuir hydrogen is dosed with 1.8 Langmuir.