The study examined the place of instructional supervision in enhancing teachers' effectiveness in public primary schools in Ebonyi State. Four research questions were formulated to guide the study. Descriptive survey research design was adopted for the study. The population of the study consists of all the 462,186 teachers including the headteachers in the 1,035 primary schools in the area of study. Stratified random sampling technique was used to select 300 teachers from 60 primary schools chosen for the study. Researcher-structured questionnaire was used for data collection. The instrument was validated and test-retest method was used for the reliability test. The scores were calculated using Pearson moment correlation coefficient and it yielded co-efficient value of 0.81. The data collected were analyzed using mean scores. Major findings of the study include that instructional supervision help teachers to improve their professional growth, use relevant instructional materials, improve their teaching methods and evaluate pupils' learning outcome appropriately. The recommendations were that government should recruit adequate qualified supervisors, provide adequate funds for supervisor support as well as for organizing workshops, seminars and conferences for teachers. Above all, erring staff should be made to face appropriate disciplinary actions.