diff --git a/src/datanode/src/sql/insert.rs b/src/datanode/src/sql/insert.rs
index b7fbfe39bc..cbc6f201b7 100644
--- a/src/datanode/src/sql/insert.rs
+++ b/src/datanode/src/sql/insert.rs
@@ -34,7 +34,7 @@ impl SqlHandler {
         stmt: Insert,
     ) -> Result<SqlRequest> {
         let columns = stmt.columns();
-        let values = stmt.values();
+        let values = stmt.values().context(ParseSqlValueSnafu)?;
         //TODO(dennis): table name may be in the form of `catalog.schema.table`,
         //   but we don't process it right now.
         let table_name = stmt.table_name();
diff --git a/src/sql/src/statements/insert.rs b/src/sql/src/statements/insert.rs
index ad9064fd0b..5ab89c7a3f 100644
--- a/src/sql/src/statements/insert.rs
+++ b/src/sql/src/statements/insert.rs
@@ -1,7 +1,8 @@
-use sqlparser::ast::{SetExpr, Statement, Values};
+use sqlparser::ast::{SetExpr, Statement, UnaryOperator, Values};
 use sqlparser::parser::ParserError;
 
 use crate::ast::{Expr, Value};
+use crate::error::{self, Result};
 
 #[derive(Debug, Clone, PartialEq, Eq)]
 pub struct Insert {
@@ -27,34 +28,59 @@ impl Insert {
         }
     }
 
-    pub fn values(&self) -> Vec<Vec<Value>> {
-        match &self.inner {
+    pub fn values(&self) -> Result<Vec<Vec<Value>>> {
+        let values = match &self.inner {
             Statement::Insert { source, .. } => match &source.body {
-                SetExpr::Values(Values(values)) => values
-                    .iter()
-                    .map(|v| {
-                        v.iter()
-                            .map(|expr| match expr {
-                                Expr::Value(v) => v.clone(),
-                                Expr::Identifier(ident) => {
-                                    Value::SingleQuotedString(ident.value.clone())
-                                }
-                                _ => unreachable!(),
-                            })
-                            .collect::<Vec<Value>>()
-                    })
-                    .collect(),
+                SetExpr::Values(Values(exprs)) => sql_exprs_to_values(exprs)?,
                 _ => unreachable!(),
             },
             _ => unreachable!(),
-        }
+        };
+        Ok(values)
     }
 }
 
+fn sql_exprs_to_values(exprs: &Vec<Vec<Expr>>) -> Result<Vec<Vec<Value>>> {
+    let mut values = Vec::with_capacity(exprs.len());
+    for es in exprs.iter() {
+        let mut vs = Vec::with_capacity(es.len());
+        for expr in es.iter() {
+            vs.push(match expr {
+                Expr::Value(v) => v.clone(),
+                Expr::Identifier(ident) => Value::SingleQuotedString(ident.value.clone()),
+                Expr::UnaryOp { op, expr }
+                    if matches!(op, UnaryOperator::Minus | UnaryOperator::Plus) =>
+                {
+                    if let Expr::Value(Value::Number(s, b)) = &**expr {
+                        match op {
+                            UnaryOperator::Minus => Value::Number(format!("-{}", s), *b),
+                            UnaryOperator::Plus => Value::Number(s.to_string(), *b),
+                            _ => unreachable!(),
+                        }
+                    } else {
+                        return error::ParseSqlValueSnafu {
+                            msg: format!("{:?}", expr),
+                        }
+                        .fail();
+                    }
+                }
+                _ => {
+                    return error::ParseSqlValueSnafu {
+                        msg: format!("{:?}", expr),
+                    }
+                    .fail()
+                }
+            });
+        }
+        values.push(vs);
+    }
+    Ok(values)
+}
+
 impl TryFrom<Statement> for Insert {
     type Error = ParserError;
 
-    fn try_from(value: Statement) -> Result<Self, Self::Error> {
+    fn try_from(value: Statement) -> std::result::Result<Self, Self::Error> {
         match value {
             Statement::Insert { .. } => Ok(Insert { inner: value }),
             unexp => Err(ParserError::ParserError(format!(
@@ -78,7 +104,37 @@ mod tests {
         let mut stmts = ParserContext::create_with_dialect(sql, &GenericDialect {}).unwrap();
         assert_eq!(1, stmts.len());
         let insert = stmts.pop().unwrap();
-        let r: Result<Statement, ParserError> = insert.try_into();
-        r.unwrap();
+        let _stmt: Statement = insert.try_into().unwrap();
+    }
+
+    #[test]
+    fn test_insert_value_with_unary_op() {
+        use crate::statements::statement::Statement;
+
+        // insert "-1"
+        let sql = "INSERT INTO my_table VALUES(-1)";
+        let stmt = ParserContext::create_with_dialect(sql, &GenericDialect {})
+            .unwrap()
+            .remove(0);
+        match stmt {
+            Statement::Insert(insert) => {
+                let values = insert.values().unwrap();
+                assert_eq!(values, vec![vec![Value::Number("-1".to_string(), false)]]);
+            }
+            _ => unreachable!(),
+        }
+
+        // insert "+1"
+        let sql = "INSERT INTO my_table VALUES(+1)";
+        let stmt = ParserContext::create_with_dialect(sql, &GenericDialect {})
+            .unwrap()
+            .remove(0);
+        match stmt {
+            Statement::Insert(insert) => {
+                let values = insert.values().unwrap();
+                assert_eq!(values, vec![vec![Value::Number("1".to_string(), false)]]);
+            }
+            _ => unreachable!(),
+        }
     }
 }