Preheat your oven to 350°F (175°C).
In a medium bowl, combine graham cracker crumbs, granulated sugar, and melted butter. Press this mixture firmly into the bottom of your lined baking pan.
In a large bowl, beat softened cream cheese until smooth. Add in pumpkin puree, brown sugar, eggs, vanilla extract, and pumpkin pie spice. Mix until well combined. Pour this mixture over your prepared crust.
In another bowl, mix together flour, rolled oats, cold cubed butter, and brown sugar until crumbly. Sprinkle this streusel over the cheesecake layer.
Place your pan in the preheated oven and bake for about 45 minutes or until the center is set. Allow to cool completely before refrigerating for at least two hours.