Children are the most vulnerable and always at increased risk of some infectious diseases in human society; thus, it is vital to monitor the occurrence of these health concerns to be able to provide appropriate medical attention and management. The Philippines, being an archipelagic country, has shown that for the past several years, based on records of the Department of Health, occurrences of both communicable and non-communicable diseases vary from region to region, and from communities to communities. To be able to have information at the local level, conditions affecting children admitted in hospitals in Iligan City, Philippines, was data-mined to be able to determine the frequencies of communicable and non-communicable diseases affecting the different age groups. Given a list of medical records available from the hospital for a period of nine years (2005 to 2013), patients ranging from 1 to 12 years old were divided into three categories: 1 to 3 years old (toddler), 4 to 5 years old (pre-school), and 6 to 12 years old (grade school). Results of the evaluation of patients’ records show thirty diseases are commonly the cause of hospital admissions. The list based on tabulated data, the number of patients that were diagnosed by these diseases concerning age and gender show the distribution of the diseases for every year shown through stacked bar graphs. Across all the years, it was found out that the most prevalent diseases among children were pneumonia, acute gastroenteritis with dehydration, and urinary tract infection. The number of incidences per year of the mentioned diseases, however, showed some variations in frequencies. Urinary tract infection and acute gastroenteritis were almost similar, while cases of pneumonia varied and were the highest in three years 2008, 2009, and 2012. These findings may be useful in making preventive measures against these diseases from occurring in the succeeding years by the government’s Department of Health and provide appropriate measures to be done by the communities in the city to avoid the incidence of high admissions due to these diseases.