diff --git a/graphql.go b/graphql.go
index f2c5b54..e0248fd 100644
--- a/graphql.go
+++ b/graphql.go
@@ -5,6 +5,7 @@ import (
 	"context"
 	"encoding/json"
 	"fmt"
+	"io/ioutil"
 	"net/http"
 
 	"github.com/shurcooL/go/ctxhttp"
@@ -70,7 +71,8 @@ func (c *Client) do(ctx context.Context, op operationType, v interface{}, variab
 	}
 	defer resp.Body.Close()
 	if resp.StatusCode != http.StatusOK {
-		return fmt.Errorf("unexpected status: %v", resp.Status)
+		body, _ := ioutil.ReadAll(resp.Body)
+		return fmt.Errorf("non-200 OK status code: %v body: %q", resp.Status, body)
 	}
 	var out struct {
 		Data   *json.RawMessage
@@ -79,11 +81,13 @@ func (c *Client) do(ctx context.Context, op operationType, v interface{}, variab
 	}
 	err = json.NewDecoder(resp.Body).Decode(&out)
 	if err != nil {
+		// TODO: Consider including response body in returned error, if deemed helpful.
 		return err
 	}
 	if out.Data != nil {
 		err := jsonutil.UnmarshalGraphQL(*out.Data, v)
 		if err != nil {
+			// TODO: Consider including response body in returned error, if deemed helpful.
 			return err
 		}
 	}
diff --git a/graphql_test.go b/graphql_test.go
index 4262c3f..e09dcc9 100644
--- a/graphql_test.go
+++ b/graphql_test.go
@@ -101,6 +101,30 @@ func TestClient_Query_noDataWithErrorResponse(t *testing.T) {
 	}
 }
 
+func TestClient_Query_errorStatusCode(t *testing.T) {
+	mux := http.NewServeMux()
+	mux.HandleFunc("/graphql", func(w http.ResponseWriter, req *http.Request) {
+		http.Error(w, "important message", http.StatusInternalServerError)
+	})
+	client := graphql.NewClient("/graphql", &http.Client{Transport: localRoundTripper{handler: mux}})
+
+	var q struct {
+		User struct {
+			Name graphql.String
+		}
+	}
+	err := client.Query(context.Background(), &q, nil)
+	if err == nil {
+		t.Fatal("got error: nil, want: non-nil")
+	}
+	if got, want := err.Error(), `non-200 OK status code: 500 Internal Server Error body: "important message\n"`; got != want {
+		t.Errorf("got error: %v, want: %v", got, want)
+	}
+	if q.User.Name != "" {
+		t.Errorf("got non-empty q.User.Name: %v", q.User.Name)
+	}
+}
+
 // Test that an empty (but non-nil) variables map is
 // handled no differently than a nil variables map.
 func TestClient_Query_emptyVariables(t *testing.T) {