diff --git a/java/google/registry/model/registry/Registry.java b/java/google/registry/model/registry/Registry.java
index 0ae1783c7..fcd7175f8 100644
--- a/java/google/registry/model/registry/Registry.java
+++ b/java/google/registry/model/registry/Registry.java
@@ -68,6 +68,7 @@ import java.util.Collection;
 import java.util.Map.Entry;
 import java.util.Optional;
 import java.util.Set;
+import java.util.regex.Pattern;
 import javax.annotation.Nullable;
 import org.joda.money.CurrencyUnit;
 import org.joda.money.Money;
@@ -852,7 +853,13 @@ public class Registry extends ImmutableObject implements Buildable {
       return this;
     }
 
+    private static final Pattern ROID_SUFFIX_PATTERN = Pattern.compile("^[A-Z0-9_]{1,8}$");
+
     public Builder setRoidSuffix(String roidSuffix) {
+      checkArgument(
+          ROID_SUFFIX_PATTERN.matcher(roidSuffix).matches(),
+          "ROID suffix must be in format %s",
+          ROID_SUFFIX_PATTERN.pattern());
       getInstance().roidSuffix = roidSuffix;
       return this;
     }
diff --git a/javatests/google/registry/model/registry/RegistryTest.java b/javatests/google/registry/model/registry/RegistryTest.java
index 3cc9e42c0..6208cfde9 100644
--- a/javatests/google/registry/model/registry/RegistryTest.java
+++ b/javatests/google/registry/model/registry/RegistryTest.java
@@ -17,7 +17,6 @@ package google.registry.model.registry;
 import static com.google.common.collect.Iterables.transform;
 import static com.google.common.truth.Truth.assertThat;
 import static com.google.common.truth.Truth.assertWithMessage;
-import static com.google.common.truth.Truth8.assertThat;
 import static google.registry.model.common.EntityGroupRoot.getCrossTldKey;
 import static google.registry.model.ofy.ObjectifyService.ofy;
 import static google.registry.model.registry.label.ReservedListTest.GET_NAME_FUNCTION;
@@ -29,6 +28,8 @@ import static google.registry.util.DateTimeUtils.END_OF_TIME;
 import static google.registry.util.DateTimeUtils.START_OF_TIME;
 import static org.joda.money.CurrencyUnit.EUR;
 import static org.joda.money.CurrencyUnit.USD;
+import static org.junit.Assert.assertThrows;
+import static org.junit.Assert.expectThrows;
 
 import com.google.common.collect.ImmutableSet;
 import com.google.common.collect.ImmutableSortedMap;
@@ -488,4 +489,27 @@ public class RegistryTest extends EntityTestCase {
         .setEapFeeSchedule(ImmutableSortedMap.of(START_OF_TIME, Money.zero(EUR)))
         .build();
   }
+
+  @Test
+  public void testFailure_roidSuffixTooLong() {
+    IllegalArgumentException e =
+        expectThrows(
+            IllegalArgumentException.class,
+            () -> Registry.get("tld").asBuilder().setRoidSuffix("123456789"));
+    assertThat(e).hasMessageThat().isEqualTo("ROID suffix must be in format ^[A-Z0-9_]{1,8}$");
+  }
+
+  @Test
+  public void testFailure_roidSuffixNotUppercased() {
+    assertThrows(
+        IllegalArgumentException.class,
+        () -> Registry.get("tld").asBuilder().setRoidSuffix("abcd"));
+  }
+
+  @Test
+  public void testFailure_roidSuffixContainsInvalidCharacters() {
+    assertThrows(
+        IllegalArgumentException.class,
+        () -> Registry.get("tld").asBuilder().setRoidSuffix("ABC-DEF"));
+  }
 }
diff --git a/javatests/google/registry/testing/DatastoreHelper.java b/javatests/google/registry/testing/DatastoreHelper.java
index 06a2dcc0c..304bed87f 100644
--- a/javatests/google/registry/testing/DatastoreHelper.java
+++ b/javatests/google/registry/testing/DatastoreHelper.java
@@ -418,10 +418,11 @@ public class DatastoreHelper {
   }
 
   public static void createTld(String tld, ImmutableSortedMap<DateTime, TldState> tldStates) {
-    createTld(
-        tld,
-        Ascii.toUpperCase(tld.replaceFirst(ACE_PREFIX_REGEX, "").replace('.', '_')),
-        tldStates);
+    // Coerce the TLD string into a valid ROID suffix.
+    String roidSuffix =
+        Ascii.toUpperCase(tld.replaceFirst(ACE_PREFIX_REGEX, "").replace('.', '_'))
+            .replace('-', '_');
+    createTld(tld, roidSuffix.length() > 8 ? roidSuffix.substring(0, 8) : roidSuffix, tldStates);
   }
 
   public static void createTld(
diff --git a/javatests/google/registry/tools/CreateTldCommandTest.java b/javatests/google/registry/tools/CreateTldCommandTest.java
index c31ccc806..60f8c1c76 100644
--- a/javatests/google/registry/tools/CreateTldCommandTest.java
+++ b/javatests/google/registry/tools/CreateTldCommandTest.java
@@ -16,7 +16,6 @@ package google.registry.tools;
 
 import static com.google.common.collect.Iterables.transform;
 import static com.google.common.truth.Truth.assertThat;
-import static com.google.common.truth.Truth8.assertThat;
 import static google.registry.model.registry.label.ReservedListTest.GET_NAME_FUNCTION;
 import static google.registry.testing.DatastoreHelper.createTld;
 import static google.registry.testing.DatastoreHelper.persistPremiumList;
@@ -78,13 +77,13 @@ public class CreateTldCommandTest extends CommandTestCase<CreateTldCommand> {
   @Test
   public void testFailure_multipleArguments() throws Exception {
     thrown.expect(IllegalArgumentException.class, "Can't create more than one TLD at a time");
-    runCommandForced("--roid_suffix=blah", "--dns_writers=VoidDnsWriter", "xn--q9jyb4c", "test");
+    runCommandForced("--roid_suffix=BLAH", "--dns_writers=VoidDnsWriter", "xn--q9jyb4c", "test");
   }
 
   @Test
   public void testFailure_multipleDuplicateArguments() throws Exception {
     thrown.expect(IllegalArgumentException.class, "Can't create more than one TLD at a time");
-    runCommandForced("--roid_suffix=blah", "--dns_writers=VoidDnsWriter", "test", "test");
+    runCommandForced("--roid_suffix=BLAH", "--dns_writers=VoidDnsWriter", "test", "test");
   }
 
   @Test