MK8 may refer to:

• Mario Kart 8, a 2014 video game by Nintendo
• Kallikrein 8, an enzyme
• The Japanese naval designation of the Mitsubishi Kinsei radial engine

• XHRNS-TV
• XHRON-TV
• XHRPS-TV
• XHRPU-FM
• XHRR-FM
• XHRRT-FM
• XHRSO-TV
• XHRST
• XHRST-FM
• XHRTA
• XHRTA-FM
• XHRT-FM
• XHRUV-FM
• XHRV-FM
• XHRW-FM
• XHRYA-FM
• XHRYN-FM
• XHRYS-FM
• XHSAC-TV
• XHSAF-FM
• XHSAM-TV
• XHSAS-TV
• XHSBC-TV
• XHSCC-TDT
• XHSCE-TV