diff --git a/schemars/Cargo.toml b/schemars/Cargo.toml
index 81d11936..3aedb494 100644
--- a/schemars/Cargo.toml
+++ b/schemars/Cargo.toml
@@ -120,5 +120,9 @@ required-features = ["smol_str"]
 name = "semver"
 required-features = ["semver"]
 
+[[test]]
+name = "decimal"
+required-features = ["rust_decimal", "bigdecimal"]
+
 [package.metadata.docs.rs]
 all-features = true
diff --git a/schemars/src/json_schema_impls/decimal.rs b/schemars/src/json_schema_impls/decimal.rs
index d7fc8a1f..4f908a2a 100644
--- a/schemars/src/json_schema_impls/decimal.rs
+++ b/schemars/src/json_schema_impls/decimal.rs
@@ -4,19 +4,20 @@ use crate::JsonSchema;
 
 macro_rules! decimal_impl {
     ($type:ty) => {
-        decimal_impl!($type => Number, "Number");
-    };
-    ($type:ty => $instance_type:ident, $name:expr) => {
         impl JsonSchema for $type {
             no_ref_schema!();
 
             fn schema_name() -> String {
-                $name.to_owned()
+                "Decimal".to_owned()
             }
 
             fn json_schema(_: &mut SchemaGenerator) -> Schema {
                 SchemaObject {
-                    instance_type: Some(InstanceType::$instance_type.into()),
+                    instance_type: Some(InstanceType::String.into()),
+                    string: Some(Box::new(StringValidation {
+                        pattern: Some(r"^-?[0-9]+(\.[0-9]+)?$".to_owned()),
+                        ..Default::default()
+                    })),
                     ..Default::default()
                 }
                 .into()
diff --git a/schemars/tests/decimal.rs b/schemars/tests/decimal.rs
new file mode 100644
index 00000000..7c3caa13
--- /dev/null
+++ b/schemars/tests/decimal.rs
@@ -0,0 +1,12 @@
+mod util;
+use util::*;
+
+#[test]
+fn rust_decimal() -> TestResult {
+    test_default_generated_schema::<rust_decimal::Decimal>("rust_decimal")
+}
+
+#[test]
+fn bigdecimal() -> TestResult {
+    test_default_generated_schema::<bigdecimal::BigDecimal>("bigdecimal")
+}
diff --git a/schemars/tests/expected/bigdecimal.json b/schemars/tests/expected/bigdecimal.json
new file mode 100644
index 00000000..855db6f7
--- /dev/null
+++ b/schemars/tests/expected/bigdecimal.json
@@ -0,0 +1,6 @@
+{
+  "$schema": "http://json-schema.org/draft-07/schema#",
+  "title": "Decimal",
+  "type": "string",
+  "pattern": "^-?[0-9]+(\\.[0-9]+)?$"
+}
\ No newline at end of file
diff --git a/schemars/tests/expected/rust_decimal.json b/schemars/tests/expected/rust_decimal.json
new file mode 100644
index 00000000..855db6f7
--- /dev/null
+++ b/schemars/tests/expected/rust_decimal.json
@@ -0,0 +1,6 @@
+{
+  "$schema": "http://json-schema.org/draft-07/schema#",
+  "title": "Decimal",
+  "type": "string",
+  "pattern": "^-?[0-9]+(\\.[0-9]+)?$"
+}
\ No newline at end of file