This research titled " effect of teaching oral expression on developing speaking skills of SIS II students in Arabic schools of Kaduna state-Nigeria”, aimed at finding the impact of teaching oral expression on developing speaking skills of SIS II students in Arabic schools of Kaduna state-Nigeria. To justify objectives of the research, the researcher stated four research questions which attempt was made in answering them and four hypotheses attempt was made in testing them. Senior Arabic Schools II in Kaduna State was used as a population of the study, quasi-experimental design was used for the research purposes. The sample of 48 students was drown from the population, they were further subdivided into two experimental group with (24) and control group (24) students, purposive sampling technique was employed in the sampling. The total number of the questions are (4), the result of the research shows that there is positive effect of teaching Oral Expression on developing speaking skills. Based on the research findings, the researcher recommends that the National Board for Arabic and Islamic Studies (NBAIS)should develop the syllabus of teaching Oral expression, and the Subject should be given special concern like other Arabic subjects such as Arabic gramma, rhetorics, morphology and others. andArabic teachers in senior Arabic schools should be always communicating with their students in Arabic language