Nigerian secondary schools are under pressure to make their impact on society through the development of values that promote civic responsibility (Iyamu and Otote, 2003). Nwankwo (2000) posits that human attitude is the greatest dimension of any national development issue. Education is one of the active media for influencing this attitude. The teaching and learning of attitude falls under the affective domain of learning. This paper found out the effect of training background of social studies teachers on their affective evaluation competencies and the extent to which such competencies can be predicted by their area of specialisation. To assess such competencies, the study sampled (84) social studies teachers from secondary schools in Edo state of Nigeria, for observation in a classroom setting. It used 20 item, four point rating scale covering the five domains of affective evaluation as identified by Kissock (1982). On analysis of data, it was found that training background of teachers when categorised at the two levels had no significant influence on teachers' evaluation of the affective domain. However, when training background was categorised into thirty two disciplines represented in the study, teachers in subject areas related to social studies demonstrated competency in affective evaluation in line with the level of relatedness of their subject areas to social studies as a discipline. Recommendations made include the need for recruitment of professionally qualified social studies teachers. Training workshops for in service teachers with emphasis on affective evaluation. (Contains 4 tables.)