Winlock () is a city in Lewis County, Washington, United States. The population was 1,339 at the 2010 census. It was named after territorial army general, Winlock M. Miller, who briefly resided there. Winlock is mostly well-known for having the World’s Largest Egg, reflecting its former status as a major producer of eggs. Early in its history, Winlock attracted many immigrants from Finland, Germany, and Sweden.

Winlock began as a Northern Pacific Railroad construction camp called Wheeler’s Camp in c. 1871. The railroad was subsequently in the process of extending its line from Kalama to Tacoma, Washington. Dr. C. C. Pagett, an upfront resident, donated the house for the townsite. In 1873, he named it for General William Winlock Miller of Olympia, a man of some renown in the area. Miller had promised to meet the expense of a hypothetical bell to the town if it were to be named after him. The town was incorporated in 1883.

Winlock is located at 46°29′29″N 122°56′15″W / 46.49139°N 122.93750°W / 46.49139; -122.93750 (46.491308, -122.937588).

According to the United States Census Bureau, the city has a total area of 1.29 square miles (3.34 km²), all of it land.

Olequa Creek, a main tributary of the Cowlitz River, runs through the center of town from north to south.