The company told Reuters it will inspect more than 250 companies which make products for Samsung after a US based group accused one of its suppliers of using child workers.
Samsung also said its audit into working conditions at an HEG Electronics facility in Huizhou in southern China found no under-aged workers.
However, New York-based China Labour Watch, which blew the whistle on Apple's use of sweatshop labour, alleged last month seven children younger than 16 were working in the factory, which makes phones and DVD players for Samsung.
Samsung did find several instances of inadequate management and potentially unsafe practices such as overtime beyond local regulations, improper safety measures and a system of fines for tardiness or absences.
If child labour was being used then Samsung would sever its contract with that company immediately, it said in a statement.
It would conduct inspections for all 105 supplier companies in China which produce goods solely for Samsung by the end of September, and review another 144 suppliers that makes products for it and other firms.