Pentavalent vaccine is a combined vaccine that can prevent a variety of diseases. Compared with the national free vaccination, the biggest difference is that it is a self-financed vaccine, which is more expensive, but it can reduce the number of times children are vaccinated, thus reducing the number of pains in children and reducing the incidence of adverse reactions after vaccination. In addition, the difference between the two is also manifested in the following points: 1. Types of diseases prevented: The pentavalent vaccine can prevent polio, diphtheria, pertussis, tetanus and Haemophilus influenzae type B infection at the same time. The free vaccine can usually be used to prevent polio, diphtheria, pertussis and tetanus, but the prevention of Haemophilus influenzae type B requires self-injection of the relevant vaccine. 2. Number of vaccinations: The DPT vaccine requires three doses of basic immunization at 2, 3 and 4 months of age or 3, 4 and 5 months of age, and one dose of booster immunization at 18 months of age, for a total of four vaccinations. The free vaccine requires infants and children to receive inactivated polio vaccine at 2 months of age; inactivated polio vaccine, polio, HIB at 3 months of age, 4 months of age, and 18 months of age; and polio, HIB at 5 months of age, for a total of 12 doses; 3. Adverse reactions: If the conventional polio vaccine is made of aluminum hydroxide adjuvant will be adsorbed on the molecular surface, which may affect the immunization effect and increase the possibility of adverse reactions The possibility of adverse reactions. The DPT vaccine is purified by inactivation of formaldehyde, and the effective antigenic components are immunologically effective, thus providing higher protective efficacy, longer protection time and fewer adverse reactions; 4. The pain sensation is lower, thus reducing abnormal crying in children and improving injection safety. Both the pentavalent vaccine and the free vaccine can play a role in preventing infectious diseases and are the most cost-effective means of preventing and controlling infectious diseases. According to the requirements of China’s immunization planning procedures, parents can voluntarily choose the DPT5 vaccine and the regular free vaccine to complete the basic immunization of infants and children as well as the booster immunization.