An elderly veteran visits the Normandy American Cemetery and Memorial with his family. At a tombstone, he falls to his knees with emotion. On the morning of June 6, 1944, American soldiers land on Omaha Beach as part of the Normandy Invasion. They suffer heavy losses in assaulting fortified German defensive positions. Captain Miller of the 2nd Ranger Battalion leads a breakout from the beach. Elsewhere on the beach, a dead soldier lies face-down in the bloody surf; his pack is stenciled Ryan, S.
In Washington, D.C., at the U.S. War Department, General George Marshall learns that three of the four sons of the Ryan family were killed in action and that the fourth son, James, is with the 101st Airborne Division somewhere in Normandy. After reading Abraham Lincoln’s Bixby letter aloud, Marshall orders Ryan brought home.
Three days after D-Day, Miller receives orders to find Ryan and bring him back. He chooses seven men from his company—T/Sgt. Horvath, Privates First Class Reiben and Caparzo, Privates Mellish and Jackson, T/4 medic Wade—plus T/5 Upham, an interpreter from headquarters. They move out to Neuville, where they meet a squad of the 101st engaged against the enemy. Caparzo is killed by a German sniper who is then killed by Jackson. They locate a Private James Ryan, only to learn that he is not the right one. From passing soldiers, Miller learns that Ryan is defending an important bridge in Ramelle.
Near Ramelle, Miller decides to neutralize a German machine gun position at a derelict radar station, despite his men’s misgivings. Wade is killed in the skirmish. At Upham’s urging, Miller declines to execute a surviving German soldier, and sets him free. Losing confidence in Miller’s leadership, Reiben declares his intention to desert, prompting a confrontation with Horvath. Miller defuses the standoff by disclosing his civilian career as a high school English teacher, about which his men had set up a betting pool; Reiben decides to stay.
At Ramelle, they find Ryan among a small group of paratroopers preparing to defend the key bridge against an imminent German attack. Miller tells Ryan that his brothers are dead, and that he was ordered to bring him home. Ryan is distressed about his brothers, but is unwilling to leave his post. Miller combines his unit with the paratroopers in defense of the bridge. He devises a plan to ambush the enemy with two .30-caliber guns, Molotov cocktails, anti-tank mines and improvised satchel charges made from socks.
Elements of the 2nd SS Panzer Division arrive with two Tiger tanks and two Marder tank destroyers, all protected by German infantry. Although they inflict heavy casualties on the Germans, most of the paratroopers, along with Jackson, Mellish and Horvath, are killed; Upham is immobilized by fear. Miller attempts to blow up the bridge, but is shot by the freed German prisoner from the radar station, who had rejoined a fighting unit. Miller crawls to retrieve the bridge detonator, and fires ineffectually but defiantly with his pistol at an oncoming tank. As the tank reaches the bridge, an American P-51 Mustang flies overhead and destroys the tank, after which American armored units arrive to rout the remaining Germans. With the Germans in full retreat, Upham emerges from hiding and shoots the German prisoner dead, having witnessed him shooting Miller, but allows his fellow soldiers to flee.
Reiben and Ryan are with the dying Miller as he utters his last words, “James… earn this. Earn it”. As Ryan stands over Miller’s body, years are added to his face and he becomes the elderly veteran standing next to Miller’s grave. Ryan asks his wife if he was worthy of such sacrifice, to which she replies that he is. Ryan salutes Miller’s grave.