The purpose of this study is to find out the effectiveness of discovery learning and enquiry learning model toward learning outcome in natural science (IPA) subject especially in chapter of plant and its part. This study was conducted on 162 students of 4th grade of elementary school in Kendali Sodo. This is an experimental study with nonequivalent posttest design. Meanwhile the sampling cluster sampling model which use 3 SD. Data analysis result using N-gain score show that mean of experiment class discovery (ecd) was 78,1057, experiment class inquiry (eci) was 76,6121 and control class was 41,7720. Meanwhile the T-test show that experiment class discovery has t value as 6,639 > from T table (1,679), and T-value enquiry class as t 6,506 > from T table (1678). Therefore it can be concluded that the discovery and inquiry models have a significant effect on student learning outcomes. The result also show that the discovery model was the model that had the most significant effect compared to the inquiry model on student learning outcomes in the natural science lesson, especially plant material and its parts.