Place the crushed pineapple in a fine-mesh strainer over a bowl. Press gently with the back of a spoon to remove as much juice as possible.
In a large mixing bowl, combine the drained pineapple with the sweetened condensed milk. Stir until everything is evenly blended.
Gently fold the thawed whipped topping into the pineapple mixture using a rubber spatula until smooth and creamy.
Spoon the prepared filling into the graham cracker crust and spread it evenly.
Cover the pie with plastic wrap or foil and refrigerate for at least 4 hours, or until firm. For best results, chill overnight.
Cut the chilled pie into slices using a sharp knife and serve cold.
