diff --git a/spring-data-cassandra/src/main/java/org/springframework/data/cassandra/core/cql/CqlIdentifier.java b/spring-data-cassandra/src/main/java/org/springframework/data/cassandra/core/cql/CqlIdentifier.java
index 6be47929d..9de0c2e26 100644
--- a/spring-data-cassandra/src/main/java/org/springframework/data/cassandra/core/cql/CqlIdentifier.java
+++ b/spring-data-cassandra/src/main/java/org/springframework/data/cassandra/core/cql/CqlIdentifier.java
@@ -177,7 +177,8 @@ public final class CqlIdentifier implements Comparable<CqlIdentifier>, Serializa
 	 * @since 2.1.10
 	 */
 	public static boolean requiresQuoting(CharSequence chars) {
-		return QUOTED.matcher(chars).matches() || ReservedKeyword.isReserved(chars);
+		return QUOTED.matcher(chars).matches() || ReservedKeyword.isReserved(chars)
+				|| (chars.length() > 0 && chars.charAt(0) == '_');
 	}
 
 	/**
diff --git a/spring-data-cassandra/src/test/java/org/springframework/data/cassandra/core/cql/CqlIdentifierUnitTests.java b/spring-data-cassandra/src/test/java/org/springframework/data/cassandra/core/cql/CqlIdentifierUnitTests.java
index 615c93a9b..e9af25778 100755
--- a/spring-data-cassandra/src/test/java/org/springframework/data/cassandra/core/cql/CqlIdentifierUnitTests.java
+++ b/spring-data-cassandra/src/test/java/org/springframework/data/cassandra/core/cql/CqlIdentifierUnitTests.java
@@ -68,7 +68,7 @@ public class CqlIdentifierUnitTests {
 
 	@Test
 	public void testIllegals() {
-		String[] illegals = new String[] { null, "", "a ", "a a", "a\"", "a'", "a''", "\"\"", "''", "-", "a-", "_", "_a" };
+		String[] illegals = new String[] { null, "", "a ", "a a", "a\"", "a'", "a''", "\"\"", "''", "-", "a-"};
 		for (String illegal : illegals) {
 			try {
 				of(illegal);
diff --git a/spring-data-cassandra/src/test/java/org/springframework/data/cassandra/core/mapping/CassandraMappingContextUnitTests.java b/spring-data-cassandra/src/test/java/org/springframework/data/cassandra/core/mapping/CassandraMappingContextUnitTests.java
index f77e2bcef..16a6f3be9 100755
--- a/spring-data-cassandra/src/test/java/org/springframework/data/cassandra/core/mapping/CassandraMappingContextUnitTests.java
+++ b/spring-data-cassandra/src/test/java/org/springframework/data/cassandra/core/mapping/CassandraMappingContextUnitTests.java
@@ -626,6 +626,15 @@ public class CassandraMappingContextUnitTests {
 		assertThat(mappingContext.usesTable(CqlIdentifier.of(tableMetadata.getName()))).isFalse();
 	}
 
+	@Test // DATACASS-747
+	public void shouldQuoteFieldName() {
+
+		BasicCassandraPersistentEntity<?> entity = mappingContext.getRequiredPersistentEntity(UnsupportedFieldNames.class);
+
+		CassandraPersistentProperty property = entity.getRequiredPersistentProperty("_ent1");
+		assertThat(property.getColumnName()).isEqualTo(CqlIdentifier.quoted("_ent1"));
+	}
+
 	@Table
 	private static class InvalidEntityWithIdAndPrimaryKeyColumn {
 		@Id String foo;
@@ -753,4 +762,9 @@ public class CassandraMappingContextUnitTests {
 		@Id String id;
 		Map<String, TupleValue> untyped;
 	}
+
+	class UnsupportedFieldNames {
+		String _ent1;
+		String _ent2;
+	}
 }