This study is a survey of the availability and usage of instructional media in teaching and learning of Junior Secondary School (JSS) Basic Science. The study involved two hundred and fifty randomly selected JSS II students and ten Basic Science teachers from five randomly selected Junior Secondary Schools in Education District V of Lagos State. The instrument for data collection was the Availability and Usage of Instructional Media Questionnaire (AAUOIMQ) for teachers and students respectively. Data collected was analyzed using descriptive statistics of frequency counts and percentages to analyze the biographical data of respondents and the inferential statistic of chi-square was used to test the stated hypotheses at 0.05 level of significance. The findings revealed that there was a significant relationship between the availability of instructional media and effective teaching and learning of JSS Basic Science and that most of the schools did not have sufficient instructional media but the available ones were effectively used. The findings also revealed that there was a significant relationship between the usage of instructional media and effective teaching and learning of JSS Basic Science. The study established that most students experienced enhanced learning when teachers use instructional media for teaching. Likewise, the findings revealed that there was a significant relationship between teachers’ competence and the selection and utilization of relevant instructional media for effective teaching and learning of JSS Basic Science. The study concluded that the use of instructional media in Basic Science teaching is of importance as they help to stimulate learners’ interest and promote understanding of science concepts.