Congenital malformations constitute a serious problem of both medical and social nature. Cleft lip and/or palate represent the most common congenital anomaly of the face that is why it is essential to know the real frequency of the described phenomenon. The aim of this paper is to determine the frequency of cleft lip and/or palate and the types of malformations that occurred in Lodz city between the years 1981-2010. Our clinic has been carrying on the studies concerning the incidence of cleft lip and/or palate since 1981. The Polish Registry of Congenital Malformations has been operating in Poland since 1 April 1997. The team has managed to obtain data, from the Registry, concerning the total number of all live born infants and the number of children with cleft lip and/or palate, who were born in Lodz, between 1998 and 2010. In years 1981-2010, 319 children, in 210 952 live born infants, were born with cleft lip and/or palate in Lodz. The isolated cleft palate was observed more frequently in girls and the unilateral cleft of lip and palate in boys. In all three decades palate clefts are more common whereas bilateral lip, alveolus and palate clefts are more infrequent. A small tendency to decrease in actual cleft lip and/or palate frequency among children, in the period of 30 years, is observed in Lodz. Over the years it has still been observed that the isolated cleft palate is the most common type of defect.