The incident occurred at around 4 pm at Sangaipeta village under Kolcharam police station limits, they said.
The deceased are all aged around 12 years, Kolcharam Inspector Rama Krishna said adding all the five bodies were retrieved from the lake.
"It seems that the boys did not know swimming," he said based on preliminary investigation.
Expressing shock and anguish over the drowning of five children, state Chief Minister N Kiran Kumar Reddy conveyed his condolences and sympathies to the bereaved family members, a release from CMO said tonight.