Introduction: Every year it is estimated that about 14 million adolescent girls give birth globally with the highest rate (143 per 1000 girls aged 15 - 19 years) in the sub-Saharan Africa. Babies born to adolescent mothers are at greater risk and are far more likely to die than those born to older women. This study therefore sets out to describe the health care seeking behaviors in a cohort of teenage mothers attending an Under-Five Clinic in a densely populated section of Freetown, Sierra Leone with a view of determining the impact of their behavior on the survival of their children. Methodology: This is a descriptively cross sectional and prospective study that involved four hundred and six mothers attending the Under-Five Clinic in the Eastern end of Freetown using semiclosed ended questionnaire which were interviewers administered between 1^st and 29^th July 2011. Result: The age of the study population ranged between 12 and 45 years, with a mean of 24.8 ± 6.3 years. Of the four hundred and six, eighty nine (21%) were teenagers (less than 20 years) with a majority (60.6%) of them being between 18 and 19 years old. Concerning the 89 teenage mothers in the study population, the majority (95.5%) did not possess the secondary school education, 42.7% were petty traders and more than a half of them (61.8%) were married. The mothers were rated low in all the activities geared towards child survival except immunization. In addition there was a delay in the initiation of complementary feeds which were also of poor quality. Fewer percentages of the mothers who had antenatal care in the hospitals delivered there. Conclusion: This study has revealed that early marriage is still common in Sierra Leone. Also the teenage mothers did not engage fully in a majority of activities that have been proven to contribute to the survival of babies in the Tropics thereby making their children vulnerable to malnutrition, measles and diarrhoeal diseases. It was recommended that the country should use recognised teenage programs aimed at urgently addressing a reduction in teenage pregnancy especially by improving the provision of education/vocational studies for the girl child.