diff --git a/app/src/main/java/org/ntlab/developrx/JavaMainActivity.java b/app/src/main/java/org/ntlab/developrx/JavaMainActivity.java
index efd03d6..a184b71 100644
--- a/app/src/main/java/org/ntlab/developrx/JavaMainActivity.java
+++ b/app/src/main/java/org/ntlab/developrx/JavaMainActivity.java
@@ -15,8 +15,11 @@
         setContentView(R.layout.activity_main_java);
 
         findViewById(R.id.flowable_btn).setOnClickListener(view -> {
-                    rxProcess.flowableReactiveStreams();
-                }
-        );
+            rxProcess.flowableReactiveStreams();
+        });
+
+        findViewById(R.id.observable_btn).setOnClickListener(view -> {
+            rxProcess.observable();
+        });
     }
 }
diff --git a/app/src/main/java/org/ntlab/developrx/JavaRxProcess.java b/app/src/main/java/org/ntlab/developrx/JavaRxProcess.java
index e2f3b3e..59ef72c 100644
--- a/app/src/main/java/org/ntlab/developrx/JavaRxProcess.java
+++ b/app/src/main/java/org/ntlab/developrx/JavaRxProcess.java
@@ -1,10 +1,14 @@
 package org.ntlab.developrx;
 
+import org.ntlab.developrx.utils.ThreadUtil;
 import org.reactivestreams.Subscriber;
 import org.reactivestreams.Subscription;
 
 import io.reactivex.BackpressureStrategy;
 import io.reactivex.Flowable;
+import io.reactivex.Observable;
+import io.reactivex.Observer;
+import io.reactivex.disposables.Disposable;
 import io.reactivex.schedulers.Schedulers;
 
 /**
@@ -54,8 +58,7 @@
                     // データを受け取った際の処理
                     @Override
                     public void onNext(String data) {
-                        String threadName = Thread.currentThread().getName();
-                        System.out.println(threadName + ": " + data);
+                        System.out.println(ThreadUtil.getCurrentThreadName() + ": " + data);
                         // 次に受け取るデータ数をリクエストする
                         this.subscription.request(1L);
                     }
@@ -63,8 +66,7 @@
                     // 完了を通知された際の処理
                     @Override
                     public void onComplete() {
-                        String threadName = Thread.currentThread().getName();
-                        System.out.println(threadName + ": 完了しました");
+                        System.out.println(ThreadUtil.getCurrentThreadName() + ": 完了しました");
                     }
 
                     // エラーを通知された際の処理
@@ -74,4 +76,47 @@
                     }
                 });
     }
+
+    /**
+     * Observable (バックプレッシャー機能なし)
+     */
+    public void observable() {
+        Observable<String> observable = Observable.create(emitter -> {
+            String[] datas = {"データ1", "データ2", "データ3", "データ4", "データ5"};
+
+            for (String data : datas) {
+                if (emitter.isDisposed()) {
+                    return;
+                }
+                emitter.onNext(data);
+            }
+
+            emitter.onComplete();
+        });
+
+        observable.observeOn(Schedulers.computation())
+                .subscribe(
+                        new Observer<String>() {
+                            @Override
+                            public void onSubscribe(Disposable disposable) {
+                                // 何もしない
+                            }
+
+                            @Override
+                            public void onNext(String item) {
+                                System.out.println(ThreadUtil.getCurrentThreadName() + ": " + item);
+                            }
+
+                            @Override
+                            public void onError(Throwable e) {
+                                e.printStackTrace();
+                            }
+
+                            @Override
+                            public void onComplete() {
+                                System.out.println(ThreadUtil.getCurrentThreadName() + ": 完了しました");
+                            }
+                        }
+                );
+    }
 }
diff --git a/app/src/main/res/layout/activity_main_java.xml b/app/src/main/res/layout/activity_main_java.xml
index dd53f60..e9845d8 100644
--- a/app/src/main/res/layout/activity_main_java.xml
+++ b/app/src/main/res/layout/activity_main_java.xml
@@ -17,6 +17,14 @@
             android:text="flowable (Reactive Streams)"
             app:layout_constraintStart_toStartOf="parent"
             app:layout_constraintTop_toTopOf="parent" />
+
+        <Button
+            android:id="@+id/observable_btn"
+            android:layout_width="wrap_content"
+            android:layout_height="wrap_content"
+            android:text="observable"
+            app:layout_constraintStart_toStartOf="parent"
+            app:layout_constraintTop_toBottomOf="@id/flowable_btn" />
     </android.support.constraint.ConstraintLayout>
 
 </ScrollView>