Students' competence in solving trigonometry has been in doubt but little attention has been given in the area of research. An assessment of students' answers to trigonometry problems is crucial to dealing with their conceptual challenges. This study employed a descriptive qualitative research design, with the goal of evaluating errors made by students when solving trigonometric problems. Ninety senior high school students were sampled for this purpose and the data collection instruments used were a Trigonometry Achievement Test (TAT) and a Semi-structured interview. The Trigonometry Achievement Test (TAT) was designed to identify the types of errors learners make when answering trigonometry problems. Data gathered from the (TAT) was analyzed and presented using descriptive statistics. In classifying students' errors, Newman's Error Hierarchy was utilized. A semi-structured interview was also conducted and aimed at identifying the root cause of students' errors. Findings showed that a greater part of student errors relate to transformation, processing skills, and comprehension. Also, teachers' methods of instruction, students' carelessness, incorrect application of trigonometric identities and formulas, overgeneralization, and a lack of practice are the primary reasons for errors. Thus, trigonometry lessons should be taught by math teachers in a more hands-on and inductive manner as students are also advised to constantly practice solving trigonometry. Our study argues that assessment of students' answers in solving trigonometry problems, recognizing the errors made and comprehending the reasons behind them will guide instructional strategies that will make trigonometry learning easier.