This research aims to describe: (1) the types of students’ speaking error onthe communicative effect taxonomy made by the eighth grade students of SMA N 1Sambungmacan Sragen; and (2) the percentages of students’ speaking error on thecommunicative effect taxonomy made by the eighth grade students of SMA N 1Sambungmacan Sragen.The method used in this research is descriptive method. The research wascarried out to the Eleventh Grade Students of SMA N 1 Sambungmacan Sragen infour days, two days in the last February (26th, 28th) and two days in the beginning ofMarch (1st, 4th). From the population, there were 26 students of class XI Science 3taken as the sample by using cluster random sampling. interview test is used as theinstrument to collect the data. Then, the data are analyzed by using error analysisprocedure which consists of collecting the data, identifying students’ errors,classifying errors, explaining errors, and evaluating errors.From the result of the analysis of students’ spoken corpus, it can beconcluded that there are numbers of error based on communicative effect taxonomywhich classified into local and global error. This study shows that most of thestudents produced local errors and only few of them produced global errors. There are1087 cases (92.67 %) of local error while only 86 cases (7.33 %) of global errorsfrom totally 1173 cases of errors. Local errors are classified into two subcategories oferrors i.e. local morphological error and local syntactical error. One thousand errors(85.25 %) found in the case of local syntactic errors while only 87 cases (7.42 %) oflocal morphological errors are discovered in this study.The factors causing errors made by the eleventh grade students of SMANegeri 1 Sambungmacan Sragen are: (1) Interlingual transfer which is caused by theinterference of their mother tongue. It happens because there is a different systembetween Indonesian and English. Habit also belongs to interlingual transfer. (2)Intralingual transfer which is a negative transfer within the target language (English).It reflects the general characteristics of rule learning such as faulty generalization,incomplete application of rules and failure to learn conditions under which rulesapply. Interlingual only has a little influence in students’ speaking error. On the otherhand, the intralingual becomes the most dominant factor that influence the students’speaking error.Keywords: error analysis, speaking, communicative effect taxonomy, descriptivestudy.