Numerous studies have investigated the difference in effectiveness between inductive and deductive approaches to teaching grammar. In the inductive approach, teachers provide examples and then guide students toward noticing the patterns of grammar rules, whereas in the deductive approach, teachers provide explicit instruction in grammar rules and then ask students to practice the sentences. Following an in-depth literature review, the teacher-researcher conducted a quasiexperimental study in a high school in Taiwan with 109 student-participants. Three types of grammar rules (gerunds, conditional clauses and relative clauses) were instructed to students through the inductive, deductive, and combined approaches. Pretest and posttest data were collected and compared. The results indicated that for conditional and relative clauses grammar rules, the combined approach leads to significantly higher performance than the others. For gerunds, students under the deductive approach had significantly higher scores. The inductive approach was the least effective approach to teaching grammar to EFL novice learners. The findings suggest that teachers designing their curricula for teaching grammar need to consider learners’ language proficiency. Future studies should focus on interactions between the three approaches.