Ganwan block one of the twelve administrative blocks of Giridih district of Jharkhand state, India, has a population (2001 census) of 88,594. Three major bridges were constructed recently which provide communication with nearby Satgawan block of Koderma district. It has very good scenic beauty. Shankar Ekka(from Ranchi) is the current Block Development Officer. The block has two villages Sandha and Serua.