Everardo Hugo Hernandez was having dinner last night in the town of Santa Cruz Xoxocotlan when a man who had entered the restaurant with another person called out his name and shot him at point blank range, the state prosecutor's office said.
Hernandez died in a hospital in the state capital of Oaxaca today, said Jaciel Vazquez Castro, coordinator of the investigative arm of the prosecutor's office.
The state lawmaker was a member of the leftist Democratic Revolution Party (PRD) that governs Oaxaca.
Oaxaca is one of Mexico's poorest states, rife with social conflicts and land disputes.