His comments will be seen as a warning to Prime Minister Tayyip Erdogan to tread carefully and seek consensus.
Even though Erdogan has not yet unveiled his plans, the parliamentary opposition and much of the judiciary have already indicated they will try to block them.
The reform is likely to aim to curb judges' powers and make it harder to ban political parties, after Erdogan's own AK Party narrowly avoided being outlawed by the Constitutional Court in 2008 for anti-secular activities.
Court Chairman Hasim Kilic told the Hurriyet newspaper in a report published on Wednesday that Turkey needed serious constitutional reform, but that this must be achieved through a broad consensus.
"Initiatives to change the constitution in Turkey in recent times have caused a lot of tension," he said. "My fear is that the judicial reform and constitutional change will come to us...
"Turkey will sooner or later reach the target of being a country of law and democracy. But we are progressing along this path with very heavy damage." The reform plan comes at a time of tension between Erdogan's AK Party and the pillars of Turkey's secular system -- the military and the judiciary.
There is also currently media speculation that Chief Prosecutor Abdurrahman Yalcinkaya could launch a fresh bid to ban the AK Party.
Erdogan has said he will take his reforms to parliament and, if they are blocked there, seek to push them through by referendum.
The confrontation with the judges, along with the detention of scores of military officers suspected of conspiring to overthrow the government, has led to speculation that Erdogan may call a snap election instead of waiting until the end of his term in mid-2011 to seek a third term.
Erdogan denies any such plans. But if the judiciary tried to block the referendum process, creating institutional deadlock, he might come under new pressure from within his party to do so.
Since it first came to power in 2002 the AK Party has repeatedly clashed with conservative, nationalist secularists who believe it aspires to make Turkey an Islamic state, something Erdogan also strongly denies.
