The present study is an attempt to find out the relationship between organizational effectiveness and academic achievement. To study organizational effectiveness, descriptive survey method was used. A total of 100 (50 from government aided and 50 privately managed) teachers of the secondary school were taken as the sample on the basis of the purposive random sampling method. School Effectiveness Questionnaire (SEQ) developed by Baldwin et al. (1993) was used to collect the data. Karl Pearson’s product moment correlation coefficient test was used to analyze the data. The findings of the study were i) There is a significant relationship between Organizational Effectiveness and Academic Achievement of secondary schools in Assam ii) There is a significant relationship between Organizational Effectiveness and Academic Achievement of Government aided secondary schools in Assam iii) There is significant relationship between Organizational Effectiveness and Academic Achievement of private secondary schools in Assam.