The ultrastructure of magnetotactic bacteria strain WD\|1 was reported.A thin sectioned profile of it clearly showed its cell wall,cell membrane,poly\|?\|hydroxybutyrates and magnetosomes.Meanwhile,the method of batch culture of strain WD\|1 was also reported,135mg/L dry cells could be gotten with this method.The energy profiles of X\|ray collected after electron excitation in SEM indicated that both dry cells and magnetosomes contained such mineral elements as P,S,Ca,Si,Al and Fe with different content.The iron content of its cells and magnetosomes was 3 07% and 84 57% respectively.