"China wholeheartedly hopes that Myanmar will push forward a democracy process that is appropriate for the country," he told the minister on Friday.
Since August, the Myanmar government has sought to stamp out public protests sparked by a sharp increase in fuel prices.
Tang, a foreign policy adviser, said China "hoped Myanmar would restore internal stability as soon as possible, properly handle issues and actively promote national reconciliation".
He said the democracy process was "in the fundamental interests of the people of Myanmar and conducive to regional peace, stability and development".
China's comments about Myanmar's path to democracy were seen as signs of growing impatience over the handling of the recent protests.
Earlier this year China's foreign ministry published an unflattering account of Myanmar's new jungle capital, Naypidaw, complaining it was remote, isolated and barren.
But China was careful not to be seen as turning against the ruling generals.
It backed Myanmar's path to democracy - drafting of a new constitution – as a way of defusing volatile tensions, a process critics said was a sham.
Beijing is one of the few foreign capitals with friendly ties to Myanmar.
China is generally hostile to Western pressure for political relaxation in other states.
Meanwhile, the UN has asked Myanmar to release more than 150 protesters detained during the fuel-price-increase demonstrations.
The call was made by three human-rights experts who said the "brutal arrests" violated international standards and should be condemned.
In a joint statement, Ambeyi Ligabo, Leandro Despouy and Paulo Sergio Pinheiro said: "It is shocking that peaceful demonstrators have received life sentences in trials without any basic guarantee of the due process of law, and that local journalists were prevented from reporting on these measures."