In developed and developing countries, most cases of acute gastroenteritis in children are caused by viruses, and rotaviruses are known as the leading cause. The aim of our study was to estimate the main circulating serotypes of rotavirus before the introduction of routine immunisation in Latvia, and to search for their possible correlation with clinical symptoms and circulating genotypes. A cross-sectional study was carried out among children who had been hospitalised in the Children’s Clinical University Hospital from April 2013 to December 2015. Genotyping was done for 462 stool samples. Among G/P combinations, the most predominant genotypes were G4P (61.3%), G9P (12.4%) and G2P (10.0%) in children of age < 5 years, G4P (45.5%), G2P (18.2%), G9P, G3P, and G1P (9.1%) in children of age > 5 years. There was a statistically significant correlation (p < 0.05) between clinical signs (vomiting, dehydration, chronic diseases) and G1P and G8P genotypes. Infants infected with genotype G4P had a statistically significant negative correlation with severity of acute gastroenteritis episodes (p < 0.05). We detected nine different rotavirus G genotypes, and two different P genotypes. G4P, G9P, and G2P were predominant. We observed correlation between the dominant genotypes and clinical manifestations of rotavirus infection.