This study investigated whether there was a significant difference between multiple intelligence instruction (MII) and traditionally designed science instruction (TDSI) on fourth grade students' understanding of concepts associated with the "Diversity of Living Things" unit. Students' intelligence types were also examined. There were two randomly-selected classes of 35 students of between 9 and 10 years old. The experimental group was instructed through Multiple Intelligence strategies while the control group employed traditional methods. The assessment tools were the Diversity of Living Things Concepts Test (DLTCT) and the Teele Inventory of Multiple Intelligences (TIMI). Before treatment, no statistically significant difference between the groups was found in terms of understanding of diversity of living things concepts. After treatment, independent t-test analysis indicated that MII produced significantly greater achievement in the understanding of diversity of living things concepts (p less than 0.05) and on students' retention of knowledge (p less than 0.05).The results of TIMI revealed that fourth grade students' most dominant intelligence was logical-mathematical intelligence both before and after treatment. However, after treatment, some variations were observed. (Contains 2 tables and 2 figures.)