East Rocky Hill is an unincorporated community and census-designated place (CDP)[7] located in Franklin Township, in Somerset County, in the U.S. state of New Jersey.[1][2] The 2010 United States census counted 469 people, 160 households, and 115 families in the CDP.There were 172 housing units at an average density of 41.3 per square mile (15.9/km2).The racial makeup was 74.20% (348) White, 7.68% (36) Black or African American, 0.00% (0) Native American, 7.04% (33) Asian, 0.00% (0) Pacific Islander, 8.96% (42) from other races, and 2.13% (10) from two or more races.Of all households, 22.5% were made up of individuals and 8.8% had someone living alone who was 65 years of age or older.