Midland County is a county located in the U.S. state of Texas. As of 2020, the population was 169,983. The county seat is Midland. The county is so named for being halfway between Fort Worth and El Paso on the Texas and Pacific Railway. Midland County is included in the Midland, TX Metropolitan Statistical Area as well as the Midland–Odessa Combin…Midland County is a county located in the U.S. state of Texas. As of 2020, the population was 169,983. The county seat is Midland. The county is so named for being halfway between Fort Worth and El Paso on the Texas and Pacific Railway. Midland County is included in the Midland, TX Metropolitan Statistical Area as well as the Midland–Odessa Combined Statistical Area.