Tandovo (Russian: Тандово) is a lake in Barabinsky District, Novosibirsk Oblast, south-central Russia.

Its waters are slightly saline. The Sugun Peninsula is a tongue of land projecting into the northern end of the lake from the northeastern shore. It is a protected area where rare plants grow .

With an area of 87.8 square kilometers (33.9 sq mi) Tandovo is one of the largest lakes in Novosibirsk Oblast. It is located in the Baraba Lowland, the southern sector of the West Siberian Plain, 33 kilometers (21 mi) SW of Barabinsk. The lake lies 8 kilometers (5.0 mi) to the north of the northeastern end of Lake Chany, in the endorheic basin between the Ob and Irtysh rivers. In the northern half of the lake, the 7 kilometers (4.3 mi) long and 0.5 kilometers (0.31 mi) wide Sugun Peninsula almost cuts Lake Tandovo in two.

The banks of Lake Tandovo are clifflike in places, reaching heights of 5 meters (16 ft) to 8 meters (26 ft). The Tandovka River flows into the eastern shore of the lake. Its waters freeze in early November and the lake stays under ice until May.

• list of lakes in Russia

• Media related to Lake Tandovo at Wikimedia Commons
• Полуостров Сугун озера Тандово