Refugee camps have very poor sanitation
Mr Lubbers, who flew to Ingushetia from Moscow, toured the giant tented camps where refugees are spending their third winter.
Refugees shown on Russian television meeting Mr Lubbers said human rights abuses had forced them to flee.
"In Russia the death penalty is suspended, but federal forces
without trial or investigations are shooting hundreds and hundreds
of innocent Chechens," said one 45-year-old woman, Maret Magamadova, one of 5,000 people in
Bella refugee camp.
Another woman wept as she told Mr Lubbers: "Here there is cold and hunger, I would gladly go home. Get them to stop the war and let us go home."
Mr Lubbers was later quoted by the Interfax news agency as saying that the Russian military should limit its presence in Chechnya to where it was really needed.
'Back on the map'
"The less incidents there are in Chechnya involving representatives of the armed forces, the faster the Chechens who fled to Ingushetia will believe that their home republic has become safe and ready to take them back," he was reported as saying.
The war in Chechnya slipped down the international agenda following the 11 September attacks in the United States, analysts say.
UNHCR spokesman Kris Janowski said before the visit that one of the reasons for Mr Lubbers' trip was "to put Chechnya back on the map".
During his three-day trip to Russia, Mr Lubbers is also expected to hold high-level talks with Russian authorities in an attempt to find a political solution for the Chechen conflict.
On Wednesday, Moscow hinted it was prepared to resume peace talks with separatist rebels on condition that they agree to disarm.
Western criticism of the Russian military campaign was toned down significantly after Moscow backed the US-led war on terror.
Russia has always defended its military campaign, insisting its troops are fighting "terrorists" in Chechnya.
Aid groups have urged Mr Lubbers to use his influence to improve the conditions for refugees.
"The plight of the displaced population lost the attention of the international community. Thousands of displaced Chechens live under unacceptable conditions in Ingushetia, and many more arrive on a daily basis," the aid group Medecins Sans Frontieres said in its statement.
More than 150,000 Chechens have left their homes for neighbouring Ingushetia since the Russian army launched its latest military campaign in 1999.
Many of them live in abandoned cowsheds, schools and factories in poor hygienic conditions.
The UNHCR says that in addition to that, around 160,000 Chechens have been displaced inside Chechnya.