The Battle of the Coral Sea, a major engagement of the Pacific Theatre of World War II, was fought 4–8 May 1942 in the waters east of New Guinea and south of the Bismarck Islands between elements of the Imperial Japanese Navy and Allied naval and air forces from the United States (U.S.) and Australia.

To extend their empire in the Pacific to the conquest of Australia, the Japanese first had to capture the naval and air center of Port Moresby on the southeast coast of New Guinea. In order to extend the reach of their air searches for Allied naval forces, they resolved to simultaneously establish a seaplane base at Tulagi in the lower Solomon Islands. The U.S. learned of the Japanese plan, known as Operation Mo, through signals intelligence and sent two United States Navy carrier task forces and a joint Australian-American cruiser force to oppose the Japanese offensive.

The result was a strategic defeat for the Japanese, since their principal goal of landing troops at Port Moresby was thwarted, but a tactical defeat for the Allies, who suffered more significant ship losses.

Because the Japanese assumed the tactical initiative, their forces are listed first.

Forces deployed

Losses in parentheses

{| class="wikitable"

|-

! Ship Type

! <br>IJN

! <br>USN

! <br>RAN

|-

| Fleet carriers (CV)

| 2

| 2 (1)

|

|-

| Light carriers (CVL)

| 1 (1)

|

|

|-

| Heavy cruisers (CA)

| 4

| 6

| 1

|-

| Light cruisers (CL)

| 2

|

| 1

|-

| Destroyers (DD)

| 15 (1)

| 13 (1)

|

|-

| Amphibious assault vessels

| 12

|

|

|-

| Auxiliaries

| 26 (3)

| 3 (1)

|

|-

|}

250px|thumb|An explosion on the US Navy aircraft carrier Lexington, damaged by a Japanese carrier air attack on 8 May, blows an aircraft off the deck into the sea.

<!--Ship losses

{| class="wikitable"

|-

! Ship Type

! <br>IJN

! <br>USN

! <br>RAN

|-

| Fleet carriers (CV)

|

|

|

|-

| Light carriers (CVL)

|

|

|

|-

| Heavy cruisers (CA)

|

|

|

|-

| Light cruisers (CL)

|

|

|

|-

| Destroyers (DD)

|

|

|

|-

| Amphibious assault vessels

|

|

|

|-

| Auxiliaries

| Wa #1<br>Wa #2<br>Tama Maru

| Neosho

|

|-

|}-->

Japanese Forces

Task Force MO <br>

Vice Admiral Shigeyoshi Inoue, Commander, Fourth Fleet in light cruiser anchored at Rabaul

Carrier Striking Force

thumb|280px|Fleet carrier Shōkaku

<!--thumb|160px|A6M "Zeke" fighter

thumb|160px|D3A "Val" dive bomber

thumb|160px|B5N "Kate" torpedo bomber-->

Vice Admiral Takeo Takagi in heavy cruiser Myōkō

: Carrier Division 5 (Rear Adm. Chūichi Hara, Officer in Tactical Command in Zuikaku) (damaged)

:::: Air Group (Lt. Cmdr. Kakuichi Takahashi)

::::: 21 Mitsubishi A6M "Zeke" fighters (Lt. Takumi Hoashi)

::::: 20 Aichi D3A Type 99 "Val" dive bombers (Lt. Masao Yamaguchi)

:::: Air Group (Lt. Cmdr. Shigekazu Shimazaki)

: Destroyer Division 5

:: 2 destroyers

::: Both : ,

: Destroyer Division 7

:: 4 destroyers

::: All / -class: , , ,

:: 1 oiler:

:: 1 transport: Azumasan Maru

:: 2 minelayers: , Kōei Maru

:: 2 destroyers: (), (),(sunk by gunfire 5 May)

:: 5 minesweepers: Wa #1 (), Wa #2 (), Hagoromo Maru, Noshiro Maru #2, Tama Maru ()

:: 2 subchasers: Toshi Maru #3, Tama Maru #8(sunk)

: Support Group/Close Cover Force

: Rear Admiral Kuninori Marumo in light cruiser Tenryū

:: Cruiser Division 18 (Rear Adm. Marumo)

::: 2 light cruisers

:::: Both : ,

:: 2 seaplane tenders

:::

:::: Air group: 12 aircraft

:::

:::: Air group (attached)

:: 3 gunboats: Keijo Maru, Seikai Maru, Nikkai Maru

:: Cruiser Division 6 (Rear Adm. Gotō)

::: 4 heavy cruisers: , , ,

:: 1 light carrier ()

: Port Moresby Invasion Group

: Rear Admiral Sadamichi Kajioka in light cruiser Yūbari

:: Transport Unit (Rear Adm. Kōsō Abe)

::: 5 Imperial Japanese Navy (IJN) transports: Mogamigawa Maru, Chōwa Maru, Goyō Maru, Akiba Maru, Shōka Maru.

:::: Embarking approximately 500 troops from the 3rd Kure SNLF plus construction specialists from the 10th Establishment Squad

::: 6 Imperial Japanese Army (IJA) transports: Asakasan Maru, China Maru, Mito Maru, Matsue Maru, Taifuku Maru, Hibi Maru

::: 5 minesweepers: W-20 (Wa #20), Hagoromo Maru, Noshiro Maru #2, Fumi Maru #2, Seki Maru #3.

::: 1 minelayer: (Capt. Inagaki Yoshiaki)

::: 1 salvage tugboat: Woshima

::: 2 oilers: Hoyo Maru,

:: Screen

::: 1 light cruiser: (Capt. Masami Ban)

::: 6 destroyers: , , , , ,

::: 1 or 2 unidentified patrol boats

Submarine Force

Captain Noboru Ishizaki

: Patrol/Scouting Group: , , , ,

: Raiding Group: ,

Air Forces

thumb|270px|Mitsubishi G4M "Betty" bomber

thumb|270px|Kawanishi H6K "Mavis" flying boat

: 25th Air Flotilla

: Rear Admiral Sadayoshi Yamada

:: 4th Air Group (based at Rabaul)

::: 17 Mitsubishi G4M Type 1 "Betty" land attack bombers

:: Tainan Air Group (based at Lae and Rabaul)

::: 18 Mitsubishi A6M Zero "Zeke"

::: &nbsp;&nbsp;6 Mitsubishi A5M "Claude" fighters (Capt. Masahisa Saitō)

:: Yokohama Air Group (based at Rabaul, Shortland Islands, and Tulagi)

::: 12 Kawanishi H6K "Mavis" reconnaissance seaplanes

::: &nbsp;&nbsp;9 Nakajima A6M2-N "Rufe" seaplane fighters

:: Genzan Air Group (based at Rabaul)

::: 25 Mitsubishi G3M Type 96 "Nell" land attack bombers

Allied Forces

Task Force 17

Rear Admiral Frank Jack Fletcher in Yorktown

: <big>Carrier Air Group (TG 17.5)</big>

: Rear Admiral Aubrey W. Fitch, Officer in Tactical Command (OTC)

:::: Air Group (Lt. Cmdr. Oscar Pederson)

::::: VF-42: 17 F4F Wildcat fighters (Lt. Cmdr. Charles R. Fenton)

::: 1 (9 × 8-in. main battery)

:::: (Capt. Benjamin Perlman)

::: 1 (9 × 8-in. main battery)

:::: (Capt. Thomas M. Shock)

:: Screen (Capt. Alexander R. Early)

::: 5 destroyers

:::: 1 (8 × 5-in. main battery)

::::: (Lt. Cmdr. Edward L. Beck)

:::: 4 (5 × 5-in. main battery)

::::: (Cmdr. George P. Hunter)

::::: (Lt. Cmdr. Charles F. Chillingworth, Jr.)

::::: (Lt. Cmdr. William P. Burfor

::::: (Lt. Cmdr. Robert H. Rogers)

150px|thumb|Rear Adm. John Gregory Crace, RAN

: <big>Support Group (TG 17.3)</big>

: Rear Admiral John Gregory Crace, RAN

:: 2 destroyers

::: (Lt. Cmdr. Willford M. Hyman†),

:::: Patrol Squadron 71 (VP-71): 6 PBY-5 Catalinas

:::: Patrol Squadron 72 (VP-72): 6 PBY-5 Catalinas

South West Pacific Area

220px|right|thumbnail|Submarine S-41

220px|right|thumbnail|Curtiss P-40 "Tomahawks"

220px|right|thumbnail|Boeing B-17 "Flying Fortress"

220px|right|thumbnail|North American B-25 "Mitchell"

General Douglas MacArthur

: <big>Allied Naval Forces</big>

: Vice Admiral Herbert F. Leary

::: Subdiv 53 (Lt. Cmdr. Elmer E. Yeomans): , , , , ,

::: Subdiv 201 (Cmdr. Ralston B. Van Zant): , , , ,

:: Task Force 44 – temporarily assigned to Task Force 17, see Task Group 17.3 above

: <big>Allied Air Forces</big>

: Lieutenant General George Brett

:: 22px United States Army Air Forces

::: 8th Pursuit Group: 26 P-39 Airacobra fighters at Archerfield, Brisbane

:::: 35th Fighter Squadron at Port Moresby

:::: 36th Fighter Squadron at Port Moresby

:::: 7th Fighter Squadron at Darwin

:::: 13th Light Bombardment Squadron: B-25 Mitchell bombers

:::: 30th Bombardment Squadron

:::: 40th Reconnaissance Squadron

:::: 93rd Bombardment Squadron

:::: 435th Bombardment Squadron

::: 22nd Bombardment Group: 48 Martin B-26 Marauders

:: Royal Australian Air Force

::: No. 11 Squadron: Consolidated PBY Catalinas

::: No. 75 Squadron: 3 Curtiss P-40s at Port Moresby

:: 30th Infantry Brigade

::: 39th Infantry Battalion

::: 49th Infantry Battalion

::: 53rd Infantry Battalion

::: 13th Field Regiment

::: 23rd Heavy Anti-Aircraft Battery

:: Papuan Infantry Battalion,