diff --git a/docparser/model.go b/docparser/model.go
index 4350862..dfcbd6c 100644
--- a/docparser/model.go
+++ b/docparser/model.go
@@ -7,6 +7,7 @@ import (
 	"io/ioutil"
 	"os"
 	"path/filepath"
+	"reflect"
 	"regexp"
 	"strings"
 
@@ -476,6 +477,17 @@ func (spec *openAPI) parseStructs(f *ast.File, tpe *ast.StructType) (interface{}
 				p.Enum = j.enum
 			}
 
+			// Only set nullable if the openapi:"nullable" tag is present
+			if p.Nullable != nil {
+				nullable := false
+				if fld.Tag != nil {
+					nullable = reflect.StructTag(fld.Tag.Value).Get("openapi") == "nullable"
+				}
+				if !nullable {
+					p.Nullable = nil
+				}
+			}
+
 			if p != nil {
 				e.Properties[j.name] = p
 			}