This is definitely one of the must do things in Oaxaca. Set in the stunning Santa Domingo church and 57 pesos for entry its a great time. Spent about 3 hours there wondering the rooms. Each different room is dedicated to a different era. Mesoamerica until present day. Lots of great artifacts and very informative (though information is all in Spanish so you will need a bit to understand the jist of whats being said). If you come to Oaxaca, definitely make the time to come here...and plus the ethnobotanical garden is right next door so can do the 2 together (though make sure you plan that to meet time well as you have to have guided tour for the garden).
If you own or manage Museo de las Culturas de Oaxaca, register now for free tools to enhance your listing, attract new reviews, and respond to reviewers.