The CLA today (13 September) said although development in national parks is needed to satisfy housing shortages, the design must be sensitive.
The comments came in response to reports that Planning Minister Nick Boles may lessen planning restrictions in protected areas.
CLA President Harry Cotterell said: "We believe rural communities in national parks are becoming embalmed due to strict planning restrictions hindering development.
"Younger households are struggling to buy property in these areas, while older generations are finding it harder to downsize due to the lack of housing available.
"It is crucial that new housing developments in national parks follow guidelines to ensure high-quality design maintaining the rural aesthetic of the area.
"The Government needs to provide examples of good practice housing design in the countryside if they are to address concerns about new house building in national parks."