Data from the Brazilian Mangalarga Marchador Breed Association, including information on 292,012 animals borned from 1949 to 2000 were used to describe population structure. Frequency tables, central tendency and variation measurements according to owner, breeder, type of registration (known and unknown pedigree), year and month of births, progeny number for stallions and mares were presented. A total of 72.6% of the animals originated from the Southeast States of Brazil. The maximum number of birth (6.7%) was observed in 1990 and approximately 90.0% of the births occurred from September to March. Concerning progeny numbers, 73.6% of the 90,018 mares produced an average of 3.8 and a maximum of 22 offsprings. For the stallions these numbers were 26.2 and 1,322, respectively. The average generation interval was 8.9 years.