This study reports on the development of a cooperative learning attitude scale for the EFL students based on expert reviews and examines its construct validity. Three rounds of expert reviews were conducted. In each round, five content experts reviewed the items and rated their relevance to the content domain and their comprehensibility. The expert panel also assigned the items to the suggested sub-scales. After item elimination and major revisions, 45 items representing five factors with perfect reviewer consensus were retained. Although the scale was developed via expert review, the authors checked the construct validity of the instrument through CFA by collecting data from 136 pre-service EFL teachers. The results suggested elimination of six more items owing to their insignificant t values or low factor loadings, which were eliminated after two reviewers recommended to. The resultant fit statistics supported a good-fitting model with t statistics and item-total correlation significant across all variables. The coefficient alpha confirmed internal consistency of the scale and that of sub-scales.