The number of teats, defined like total number of teats measurable on left and right milk strip without between teats was evaluated. The data were provided by Czech pig breeders association and by nucleus and multiplier herd’s data of reproduction, which were consequently transferred into electronic form. In order to preserve of sufficient variability of trait, no limit values on number of teats has been set. The resulting data set was created by combining two data sources (the performance testing data and nucleus and multiplier herd’s data). Altogether, 78 867 animals with teats number collected during 1995 2015 were used in analyses. Genetic parameters were estimated for all animals in data set, separately for young boars and gilts and separately for Czech Large white (CLW) and Czech Landrase (CL) breed. The random effect of litter the animal explains only few part of the total variability of trait (4 to 7 per cent). The heritability coefficient estimated for all animals in data set was 0.35 with standard error of 0.03. The heritability coefficients estimated only for young gilts was 0.33, whereas heritability for young boars was little lower (0.30). Differences between heritability coefficients for evaluated breeds were negligible (0.36 and 0.35 for CLW and CL, respectively). All estimated coefficients of heritability reached intermediate values, little lower than other authors presents. It can be assumed the selection based on breeding values for number of teats brings their increasing in population within several generations.