Objective: To investigate the recessive infection rate of healthy children and guardians in different epidemic periods of hand, foot and mouth disease (HFMD) in Qingdao, analyze the risk factors affecting recessive infection, so as to provide the basis for HFMD prevention and control. Methods: In the nonepidemic period of 2022, the random cluster sampling method was used to selected 546 children and guardians from 4 childcare institutions in Laoshan District and Pingdu City. In the epidemic period of 2023, 690 children and guardians were selected from 6 childcare institutions in Shibei District, Laoshan District and Pingdu District. A questionnair survey was conducted in the epidemic period. Logistic regression analysis was used to analyze the factors affecting the recessive infection. Dominance analysis was used to explore the relative importance of the risk factors affecting recessive infection. Results: The results showed that the recessive infection rates of healthy children and guardians in the epidemic period were 18.84% and 13.62%, respectively; the recessive infection rates were 9.09% and 4.44% in the nonepidemic period, respectively. The results of multivariate Logistic analysis showed that rural areas (OR=4.71, 95%CI=2.57-8.61) and recessive infection of guardians (OR=18.62, 95%CI=7.45-46.56) were positively correlated with recessive infection of HFMD in healthy children (P<0.05). Washing hands (OR=0.09, 95%CI=0.04-0.20), using towels alone (OR=0.17, 95%CI=0.07-0.40), and EV71 vaccination (OR=0.42, 95%CI=0.20-0.87) were negatively correlated with recessive infection of HFMD in healthy children (P<0.05). Public toilets (OR=3.02, 95%CI=1.50-6.09) and drying bedding once per quarter (OR=3.89, 95%CI=1.75-8.68) were positively correlated with recessive infection of HFMD in healthy guardians. Housing with good lighting (OR=0.31, 95%CI=0.12-0.79), and tableware disinfection (OR=0.31, 95%CI=0.15-0.65) were negatively correlated with recessive infection of HFMD in healthy guardians (P<0.05). The results showed that recessive infection of guardians was relatively the most important for healthy children (41.51%), and tableware disinfection was relatively the most important for recessive infection of guardians (28.87%). Conclusions The recessive infections of HFMD are common among healthy populations in Qingdao, and the recessive infection rate among children during the epidemic period is relatively higher. Guardians play an important role in the recessive infection of healthy children. Therefore, healthy education should be strengthened for key populations, especially to enhance parents awareness of prevention and control to reduce the occurrence of recessive infections of hand, foot and mouth disease in children and guardians.