diff --git a/backend/src/main/java/com/festago/festival/domain/Festival.java b/backend/src/main/java/com/festago/festival/domain/Festival.java
index 5cc47311f..44b7bd684 100644
--- a/backend/src/main/java/com/festago/festival/domain/Festival.java
+++ b/backend/src/main/java/com/festago/festival/domain/Festival.java
@@ -41,6 +41,7 @@ public class Festival extends BaseTimeEntity {
     @Size(max = 255)
     private String thumbnail;
 
+    @NotNull
     @ManyToOne(fetch = FetchType.LAZY)
     private School school;
 
diff --git a/backend/src/main/java/com/festago/ticket/domain/Ticket.java b/backend/src/main/java/com/festago/ticket/domain/Ticket.java
index 1e22d76e9..b371db699 100644
--- a/backend/src/main/java/com/festago/ticket/domain/Ticket.java
+++ b/backend/src/main/java/com/festago/ticket/domain/Ticket.java
@@ -42,6 +42,7 @@ public class Ticket extends BaseTimeEntity {
     @ManyToOne(fetch = FetchType.LAZY)
     private Stage stage;
 
+    @NotNull
     private Long schoolId;
 
     @NotNull
diff --git a/backend/src/main/resources/db/migration/V6__school_notnull.sql b/backend/src/main/resources/db/migration/V6__school_notnull.sql
new file mode 100644
index 000000000..51735574f
--- /dev/null
+++ b/backend/src/main/resources/db/migration/V6__school_notnull.sql
@@ -0,0 +1,5 @@
+alter table festival
+    modify school_id bigint not null;
+
+alter table ticket
+    modify school_id bigint not null;