NACC commissioner Preecha Lertkamolmas said Supoj was given 15 days to defend himself with the anti-graft body.
Preecha said Supoj signed his name to acknowledge the charge and his cooperation with the NACC. Supoj told the comission he might seek an extension of the 15 days as he would need evidence from banks and other government agencies.
The NACC launched the probe against Supoj after thieves who broke into his house told police they discovered Supoj was keeping more than Bt1 billion in his house.
Police have retrieved about Bt18 million from the thieves but Supoj insisted that only Bt5 million had been stolen.
Preecha said Supoj was ordered to explain the source of the cash reportedly in his house and to declare all his bank accounts, his land and vehicles.