Multicultural Education Volume 9, Issue 1, 2023 _______________________________________________________________________________________ 18 Students’ Conceptual Error and Procedural Error in Solving Algebraic Problems Lusiana Delastri, Enos Lolang Article Info Abstract Article History Received: October 03 , 2022 In solving algebraic problems, there are two possible student answers, namely right or wrong. However, the correct answer is not necessarily through a process that is in accordance with the actual concept or what is called pseudo. Errors and pseudospheres made by students when solving algebraic problems can be grouped into conceptual errors and procedural errors. Conceptual errors and procedural errors are mistake that cannot be ignored in the learning of prospective mathematics teachers. Teachers need to identify these errors in order to provide corrective or corrective instructions. The purpose of this study was to identify and characterize the types of student errors in solving algebraic problems and to describe students' conceptual and procedural errors in solving algebraic problems. The design used for this research is a mixed method. There are two stages in this research. The first stage, identifying and characterizing the types of student errors in solving algebraic problems. The second stage, describes students' conceptual errors and procedural errors in solving algebraic problems. The subjects of this study were 92 students of the Mathematics Education Study Program at a university in South Sulawesi. The results of the study show that conceptual errors in algebra are caused by misconceptions about certain concepts, making equivalence between several concepts without regard to conditions, and ambiguity in interpreting mathematical symbols. Meanwhile, procedural errors are more errors at the completion stage due to the generalization of the rules. Accepted: January 06, 2023 Keywords : Algebra, Conceptual error, Procedural errors DOI: 10.5281/zenodo.7508092 Introduction Algebra is one of the topics in school mathematics which is important to study (Erbilgin & Şahin, 2021; Jin & Wong, 2015; Lee et al., 2020). It is useful in science, engineering, and calculation. In algebra there is manipulation symbol, so that an expression can be transformed into another expression by certain rules without changing the meaning. This feature makes algebra a powerful tool for solving mathematical problems and even problems in everyday life. Despite the benefits, it is generally found that a child shows aversion to Algebra. Many argue that learning Algebra is more difficult than learning to count (Guler & Celik, 2021). In solving algebraic problems, students are more likely to work procedurally without identifying the relational elements formed in the expression. One of the errors that are still often encountered is when students are asked to determine the solution of the equation 4x + 6 = 2(2x + 3).There are still students who have difficulties. Students don't know what to do with the loss of the xchanger which shows their understanding is still very shallow. Where they do not see that the object generated in the first step 4x + 6 = 4x + 6 shows that the expression in the left field is equal to the expressei in the right field. Teacher must carefully predict the student's understanding, lest his understanding only be seen in routine matters.In learning, students seem to understand mathematical problems, as if indicating that they have a deep understanding of the material, especially algebra. When solving algebraic problems, there are only two possible answers of students, namely right or wrong. But the correct answer, not necessarily through the process that corresponds to the actual concept or the so-called pseudo. Pseudo means as if someone's answer is correct, but after searching, it turns out that what the person thinks does not correspond to the substance of the concept (Subanji & Nusantara, 2013). Mistakes and pseudo-made by students when solving algebraic problems can be grouped into conceptual errors and procedural errors. Conceptual Error is an error caused by misconceptions or a wrong understanding of the principles and ideas underlying mathematical problems (for example, the relationship between numbers, characteristics, and properties of forms)(Lai, n.d.). Conceptual Error occurs because the student has misunderstood the underlying concept or has used the wrong logic (Chamundeswari, 2014). In solving problems, maybe all mathematical calculations are correct but if you understand a concept wrong, it can result in the use of the wrong procedur. Conceptual Error is the most difficult error to identify at first glance, it is also the most difficult error to recognize but it is the most important error to catch and correct.