Lianshui County () is under the administration of Huai'an, Jiangsu province, China. The northernmost county-level division of Huai'an, it borders the prefecture-level cities of Lianyungang to the north, Yancheng to the east, and Suqian to the west.
At present, Lianshui County has 17 towns and 2 townships.
The average annual temperature in Lianshui County is . The extreme maximum temperature was on 7 August 1966, and the extreme minimum temperature was on 6 February 1969. The average annual precipitation is