Mundal Lagoon (Sinhalese: මුන්දලම කලපුව,Tamil: முந்தல், Muntal) is a lagoon in Puttalam District, western Sri Lanka. The lagoon is sometimes referred to as Mundal Lake.The lagoon is linked to Puttalam Lagoon to the north by a channel. The lagoon's water is brackish.The lagoon is surrounded by a region containing rice paddies, coconut plantations and scrubland. The land is used for prawn fishing and rice cultivation.The lagoon has mangrove swamps, salt marshes and sea grasses.