Sunnyside is an unincorporated community in Castro County, Texas, United States.

[1] According to the Handbook of Texas, the community had an estimated population of 80 in 2000.

Sunnyside is located on U.S. Route 385, 15 mi (24 km) south of Dimmitt in Castro County.

[2] Today, the community is served by the Dimmitt Independent School District and the Springlake-Earth Independent School District.