diff --git a/sw/qa/extras/htmlimport/data/tdf121049-subscript-class.html b/sw/qa/extras/htmlimport/data/tdf121049-subscript-class.html
new file mode 100644
index 000000000000..aa248232079f
--- /dev/null
+++ b/sw/qa/extras/htmlimport/data/tdf121049-subscript-class.html
@@ -0,0 +1 @@
+<p><sub class="sub">sub</sub></p>
diff --git a/sw/qa/extras/htmlimport/data/tdf121049-superscript-class.html b/sw/qa/extras/htmlimport/data/tdf121049-superscript-class.html
new file mode 100644
index 000000000000..fce537d0fd0f
--- /dev/null
+++ b/sw/qa/extras/htmlimport/data/tdf121049-superscript-class.html
@@ -0,0 +1 @@
+<p><sup class="sup">sup</sup></p>
diff --git a/sw/qa/extras/htmlimport/htmlimport.cxx b/sw/qa/extras/htmlimport/htmlimport.cxx
index c624ef8a1970..dcf6aea64efd 100644
--- a/sw/qa/extras/htmlimport/htmlimport.cxx
+++ b/sw/qa/extras/htmlimport/htmlimport.cxx
@@ -9,6 +9,8 @@
 
 #include <swmodeltestbase.hxx>
 
+#include <editeng/escapementitem.hxx>
+
 #include <com/sun/star/awt/FontSlant.hpp>
 #include <com/sun/star/awt/FontUnderline.hpp>
 #include <com/sun/star/awt/FontStrikeout.hpp>
@@ -342,6 +344,30 @@ CPPUNIT_TEST_FIXTURE(HtmlImportTest, testTdf80194_subscript)
     CPPUNIT_ASSERT( 70 < getProperty<sal_Int8>(xRun, u"CharEscapementHeight"_ustr));
 }
 
+CPPUNIT_TEST_FIXTURE(HtmlImportTest, testTdf121049Superscript)
+{
+    createSwWebDoc("tdf121049-superscript-class.html");
+
+    // Without the accompanying fix in place, this test would have failed with:
+    // - Expected: 33 (DFLT_ESC_SUPER)
+    // - Actual  :  0 (SvxEscapement::Off)
+    CPPUNIT_ASSERT_EQUAL_MESSAGE(
+        "Superscript for <sup> missing", sal_Int32(DFLT_ESC_SUPER),
+        getProperty<sal_Int32>(getRun(getParagraph(1), 1), u"CharEscapement"_ustr));
+}
+
+CPPUNIT_TEST_FIXTURE(HtmlImportTest, testTdf121049Subscript)
+{
+    createSwWebDoc("tdf121049-subscript-class.html");
+
+    // Without the accompanying fix in place, this test would have failed with:
+    // - Expected: -8 (DFLT_ESC_SUB)
+    // - Actual  :  0 (SvxEscapement::Off)
+    CPPUNIT_ASSERT_EQUAL_MESSAGE(
+        "Subscript for <sub> missing", sal_Int32(DFLT_ESC_SUB),
+        getProperty<sal_Int32>(getRun(getParagraph(1), 1), u"CharEscapement"_ustr));
+}
+
 CPPUNIT_TEST_FIXTURE(HtmlImportTest, testReqIfTable)
 {
     setImportFilterName(TestFilter::HTML_WRITER);
diff --git a/sw/source/filter/html/htmlcss1.cxx b/sw/source/filter/html/htmlcss1.cxx
index b96a8b119ca7..52b43bac388e 100644
--- a/sw/source/filter/html/htmlcss1.cxx
+++ b/sw/source/filter/html/htmlcss1.cxx
@@ -77,6 +77,8 @@ const sal_uInt16 aItemIds[] =
     RES_BREAK,
     RES_PAGEDESC,
     RES_KEEP,
+    // tdf#121049 - preserve superscript/subscript when pasting HTML with class definition
+    RES_CHRATR_ESCAPEMENT,
 };
 
 void SwCSS1Parser::ChgPageDesc( const SwPageDesc *pPageDesc,