diff --git a/src/main/java/com/example/api/DTO/CamStateDTOs.java b/src/main/java/com/example/api/DTO/CamStateDTOs.java
new file mode 100644
index 0000000..9e1643e
--- /dev/null
+++ b/src/main/java/com/example/api/DTO/CamStateDTOs.java
@@ -0,0 +1,19 @@
+package com.example.api.DTO;
+
+import com.example.api.Entity.CamStateType;
+import jakarta.validation.constraints.NotNull;
+
+import java.time.Instant;
+
+public class CamStateDTOs {
+
+    public record UpdateRequest(
+            @NotNull
+            CamStateType state
+    ) {}
+
+    public record StateResponse(
+            String state,
+            Instant updatedAt
+    ) {}
+}
diff --git a/src/main/java/com/example/api/Entity/CamState.java b/src/main/java/com/example/api/Entity/CamState.java
new file mode 100644
index 0000000..e282bda
--- /dev/null
+++ b/src/main/java/com/example/api/Entity/CamState.java
@@ -0,0 +1,23 @@
+package com.example.api.Entity;
+
+import jakarta.persistence.*;
+import lombok.Getter;
+import lombok.Setter;
+
+import java.time.Instant;
+
+@Entity
+@Table(name = "cam_state")
+@Getter @Setter
+public class CamState {
+
+    @Id
+    private Long id; // Always 1 — singleton record
+
+    @Enumerated(EnumType.STRING)
+    @Column(nullable = false, length = 20)
+    private CamStateType state; // WATCHING, NOTWATCHING
+
+    @Column(nullable = false)
+    private Instant updatedAt;
+}
diff --git a/src/main/java/com/example/api/Entity/CamStateType.java b/src/main/java/com/example/api/Entity/CamStateType.java
new file mode 100644
index 0000000..0611c36
--- /dev/null
+++ b/src/main/java/com/example/api/Entity/CamStateType.java
@@ -0,0 +1,5 @@
+package com.example.api.Entity;
+
+public enum CamStateType {
+    WATCHING, NOTWATCHING
+}
diff --git a/src/main/java/com/example/api/Repository/CamStateRepository.java b/src/main/java/com/example/api/Repository/CamStateRepository.java
new file mode 100644
index 0000000..e826b31
--- /dev/null
+++ b/src/main/java/com/example/api/Repository/CamStateRepository.java
@@ -0,0 +1,7 @@
+package com.example.api.Repository;
+
+import com.example.api.Entity.CamState;
+import org.springframework.data.jpa.repository.JpaRepository;
+
+public interface CamStateRepository extends JpaRepository<CamState, Long> {
+}
diff --git a/src/main/java/com/example/api/Service/CamStateService.java b/src/main/java/com/example/api/Service/CamStateService.java
new file mode 100644
index 0000000..53537ba
--- /dev/null
+++ b/src/main/java/com/example/api/Service/CamStateService.java
@@ -0,0 +1,41 @@
+package com.example.api.Service;
+
+import com.example.api.DTO.CamStateDTOs;
+import com.example.api.Entity.CamState;
+import com.example.api.Entity.CamStateType;
+import com.example.api.Repository.CamStateRepository;
+import lombok.RequiredArgsConstructor;
+import org.springframework.stereotype.Service;
+import org.springframework.transaction.annotation.Transactional;
+
+import java.time.Instant;
+
+@Service
+@RequiredArgsConstructor
+public class CamStateService {
+
+    private static final long SINGLETON_ID = 1L;
+
+    private final CamStateRepository camStateRepository;
+
+    @Transactional(readOnly = true)
+    public CamStateDTOs.StateResponse getState() {
+        return camStateRepository.findById(SINGLETON_ID)
+                .map(s -> new CamStateDTOs.StateResponse(s.getState().name(), s.getUpdatedAt()))
+                .orElse(new CamStateDTOs.StateResponse(CamStateType.NOTWATCHING.name(), null));
+    }
+
+    @Transactional
+    public CamStateDTOs.StateResponse updateState(CamStateType state) {
+        CamState camState = camStateRepository.findById(SINGLETON_ID)
+                .orElseGet(() -> {
+                    CamState s = new CamState();
+                    s.setId(SINGLETON_ID);
+                    return s;
+                });
+        camState.setState(state);
+        camState.setUpdatedAt(Instant.now());
+        camStateRepository.save(camState);
+        return new CamStateDTOs.StateResponse(camState.getState().name(), camState.getUpdatedAt());
+    }
+}
diff --git a/src/main/java/com/example/api/controller/CamStateController.java b/src/main/java/com/example/api/controller/CamStateController.java
new file mode 100644
index 0000000..1a8f72c
--- /dev/null
+++ b/src/main/java/com/example/api/controller/CamStateController.java
@@ -0,0 +1,29 @@
+package com.example.api.controller;
+
+import com.example.api.DTO.CamStateDTOs;
+import com.example.api.Service.CamStateService;
+import jakarta.validation.Valid;
+import lombok.RequiredArgsConstructor;
+import org.springframework.http.ResponseEntity;
+import org.springframework.web.bind.annotation.*;
+
+@RestController
+@RequiredArgsConstructor
+@RequestMapping("/api/cam")
+public class CamStateController {
+
+    private final CamStateService camStateService;
+
+    // 현재 관찰 상태 조회
+    @GetMapping("/state")
+    public ResponseEntity<CamStateDTOs.StateResponse> getState() {
+        return ResponseEntity.ok(camStateService.getState());
+    }
+
+    // 관찰 상태 갱신
+    @PutMapping("/state")
+    public ResponseEntity<CamStateDTOs.StateResponse> updateState(
+            @Valid @RequestBody CamStateDTOs.UpdateRequest req) {
+        return ResponseEntity.ok(camStateService.updateState(req.state()));
+    }
+}