Does this memory foam mattress need a box spring?

No box spring is required. This is an all-foam bed on a 7-inch Serta Foam Core, so it needs a firm, flat surface: a platform bed, slats spaced under 3 inches apart, or a solid foundation. A traditional sprung box spring flexes under memory foam and can create premature body impressions, so avoid one. At 14 inches tall, a low platform keeps the climb-in height comfortable.