diff --git a/datafusion/src/optimizer/simplify_expressions.rs b/datafusion/src/optimizer/simplify_expressions.rs
index f629eaf95b5f4..7c9e976d1d0bb 100644
--- a/datafusion/src/optimizer/simplify_expressions.rs
+++ b/datafusion/src/optimizer/simplify_expressions.rs
@@ -251,6 +251,25 @@ fn simplify(expr: &Expr) -> Expr {
             op: *op,
             right: Box::new(simplify(right)),
         },
+        Expr::InList {
+            expr,
+            list,
+            negated,
+        } if list.len() >= 1 && list.len() <= 2 => {
+            if *negated {
+                list.iter()
+                    .skip(1)
+                    .fold((**expr).clone().not_eq(list[0].clone()), |acc, e| {
+                        acc.and((**expr).clone().not_eq(e.clone()))
+                    })
+            } else {
+                list.iter()
+                    .skip(1)
+                    .fold((**expr).clone().eq(list[0].clone()), |acc, e| {
+                        acc.or((**expr).clone().eq(e.clone()))
+                    })
+            }
+        }
         _ => expr.clone(),
     }
 }
@@ -293,7 +312,9 @@ impl SimplifyExpressions {
 #[cfg(test)]
 mod tests {
     use super::*;
-    use crate::logical_plan::{and, binary_expr, col, lit, Expr, LogicalPlanBuilder};
+    use crate::logical_plan::{
+        and, binary_expr, col, in_list, lit, Expr, LogicalPlanBuilder,
+    };
     use crate::test::*;
 
     fn assert_optimized_plan_eq(plan: &LogicalPlan, expected: &str) {
@@ -396,6 +417,33 @@ mod tests {
         Ok(())
     }
 
+    #[test]
+    fn simplify_inlist() -> Result<()> {
+        let expr = in_list(col("c"), vec![lit(1), lit(2)], false);
+        let expected = col("c").eq(lit(1)).or(col("c").eq(lit(2)));
+
+        assert_eq!(simplify(&expr), expected);
+        Ok(())
+    }
+
+    #[test]
+    fn simplify_inlist_negated() -> Result<()> {
+        let expr = in_list(col("c"), vec![lit(1), lit(2)], true);
+        let expected = col("c").not_eq(lit(1)).and(col("c").not_eq(lit(2)));
+
+        assert_eq!(simplify(&expr), expected);
+        Ok(())
+    }
+
+    #[test]
+    fn simplify_inlist_single() -> Result<()> {
+        let expr = in_list(col("c"), vec![lit(1)], false);
+        let expected = col("c").eq(lit(1));
+
+        assert_eq!(simplify(&expr), expected);
+        Ok(())
+    }
+
     #[test]
     fn test_simplify_simple_and() -> Result<()> {
         // (c > 5) AND (c > 5)