Stora Träsket Nature Reserve (Swedish: Stora Träskets naturreservat) is a nature reserve in Botkyrka Municipality close to Stockholm, Sweden.

The nature reserve protects an area of wildlife around the lake Stora Träsket.

The lake, with a maximum depth of 2 metres (6.6 ft) is naturally becoming smaller with time, supporting large areas of reeds and floating mats at its fringes.

On land, the lake is surrounded by old-growth forest containing several species which are used to identify areas of high ecological value; these include Goodyera repens, Chimaphila umbellata and Geastrum pectinatum, among others.

[1][2] The hiking trail Sörmlandsleden passes through the nature reserve.