The anti-EGFR antibody Nimotuzumab was radioiodinated with I-131 by Chloramine T and Iodogen methods. The ¹³¹I-Nimotuzumab was purified and characterized by HPLC. Purified ¹³¹I-Nimotuzumab exhibited radiochemical purity of >95% and retained good in vitro stability upto 24 h at room temperature by both the methods. Cell binding studies carried out in A431 cells expressing EGF receptors showed good immunoreactivity of the product upto 5 days post radioiodination. Biodistribution studies in normal Swiss mice showed fast clearance by both renal and gastrointestinal routes with minimal thyroid uptake.