This study examines the effects of learning conditions (implicit learning condition and explicit learning condition) and task types (comprehension and production task) on the learning of an easy rule (subject-verb inversion in the sentence with location adverbial) and a hard rule (pseudo-cleft clause). One hundred thirty first-year university EFL students with low proficiency were divided into four groups based on the combination of learning conditions and task types. After that, pre-and post-test data on the grammaticality judgement test and controlled written test were analyzed by using the two-way Multiple Analysis of Covariance (MANCOVA). Results showed that the effects of learning conditions are not statistically different on the comprehension of easy and hard grammatical rules whereas the explicit learning condition has more effects on producing easy and hard rules than the implicit learning condition does. They also revealed that the effects of task types are statistically different on the learning of an easy and a hard rule. In addition, production task has more effects on the learning of both an easy and a hard rule than the comprehension task. It could be suggested that the results of this study could be applied in designing more effective instructional condition for the EFL adult learners with low proficiency.