Monterey Bay League (MBL) was a high school athletic conference part of the CIF Central Coast Section of the California Interscholastic Federation. It comprised high schools generally around Monterey County, California, with schools from southern Santa Clara County, Watsonville on the edge of Santa Cruz County and one of only two high schools in San Benito County. Not all schools participated in all sports. In 2017, Monterey Bay League merged with the Mission Trail Athletic League (MTAL) to create the Pacific Coast Athletic League (PCAL).