This study aims to determine the types of metals and their levels in the samples of Blood Clams (Anadara granosa) and Feather Shells (Anadara antiquata) from the sea of Lewoleba Bay, Lembata district, East Nusa Tenggara province. Both types of shellfish live on Slug Island (Awololong) in the middle of the Lewoleba Bay marine area. The people of Lembata use the two types of shellfish as side dishes and a source of economic income. It is necessary to analyze heavy metal contamination in the marine area of Lewoleba Bay through these two types of shells because human activities have been increasing in the Lewoleba Bay area of Lembata. A total of 100 grams of each sample of dried mussel meat, was destroyed and analyzed for the content of elements and levels of elements, using an X-ray Fluorescence (XRF) spectrophotometer. The results obtained were that the Blood Shellfish sample contained the following elements and levels: P (10%), S (12%), K (12%), Ca (23%), Cr (0.32%), Fe (2 .6%), Ni (0.2%), Cu (0.62%), Zn (20.6%), Br (3.4%), Mo (14%) and Yb (0.9%) . Reed Shells samples contain; P (11.0%), S (1.0%), K (11.7%), Ca (39.2%), Cr (0.62%), Fe (8.95%), Ni ( 0.4%), Cu (0.49%), Zn (2.4%), Br (1.4%), Mo (22%) and Yb (0.3%) and Re (0.5% ). It appears that both types of samples contain essential heavy metals in the form of Cu, Fe, Zn and Ni, and contain Cr which is toxic. The Cr content in the Reed Shells samples was higher than that of Blood Clams. The Reed Shells sample also contains the element Re which is a type of rare earth element. Heavy metal levels of Cu, Ni and Cr in both samples exceeded the threshold according to the Decree of the Minister of the Environment of the Republic of Indonesia number 51 of 2004.
