Abstract: Research focusing attitudes of students toward Social Studies have dealt with interest and usefulness of the subject. There are little or no validated instruments to measure other dimensions of students` attitudes toward the subject. The purpose of this study is to develop an instrument for measuring junior secondary school students` attitudes toward Social Studies. Based on an earlier study and literature search, items initially generated were content validated, and yielded a 62-item instrument. The instrument was later on administered to 1,630 students in the final year of the Junior Secondary School. Students responded to each item on a 4-point Likert type scale ranging from strongly agree - 4, agree-3, disagree-2 to strongly disagree - 1. Factor analysis yielded 4 dimensions. The entire scale yielded a reliability of 0.93, while its sub-scales` reliability indices range between 0.73 and 0.89.