"While in public office, I did not establish any commercial organizations or own shares or share blocks in any companies," said Kasyanov, who is vacationing overseas.
Kasyanov also said his current commercial activities were conducted entirely in line with the law.
However, Kasyanov did not respond specifically to the dacha acquisition accusation in his statement.
Backed by an opposition alliance, Kasyanov has not denied that he intends to run for the presidency in 2008 elections. He said he still held the same political views.
"I still believe the current political line is wrong," the ex-premier said.
Kasyanov is not going to interrupt his vacation with his family and will return to Moscow on July 25, said his press secretary.
Kasyanov is accused of acquiring an elite land plot in Moscow via a firm that allegedly belonged to him. If convicted, he faces up to five years in prison.