"A car bomb exploded in the Ghazi Ayyash neighbourhood of Deir Ezzor," said the television, adding the blast was carried out by a "terrorist suicide bomber" and caused widespread "material damage."
It did not specify on the number of people hurt.
The explosion went off on a road housing a military and air force intelligence headquarters, and a military hospital, said the Syrian Observatory for Human Rights.
Images broadcast on state television showed a large bloodstain on the ground, a damaged building and vehicles charred by the blast, as well as smoke rising from the targeted district.
The attack, the first of its kind in Deir Ezzor since an anti-regime uprising broke out in Syria in March last year.
It came a day after Syrian troops foiled a would-be car bombing in the same city, which is about 110 kilometres (70 miles) upstream from the Iraqi border on the Euphrates river.
Elsewhere, a rocket slammed into ruling Baath party offices in northern Aleppo province on Saturday, a monitoring group said, a day after unprecedented anti-regime protests in the provincial capital of the same name.
"Unidentified gunmen targeted a Baath party office in Aleppo's Al-Bab town with a rocket-propelled grenade," the Observatory said.
Immediately after the Aleppo attack, clashes broke out between the gunmen and guards, but there were no reports of any casualties.
In Jabal Azzawya, in the flashpoint northwestern province of Idlib, clashes caused an unknown number of casualties, the Britain-based watchdog said, after a series of explosions were heard in the restive area.
The rights group added that three military vehicles were targeted in Jabal Azzawya, while one of the attacks was carried out with a rocket-propelled grenade.
On the outskirts of Sarmada town, also in Idlib province, clashes broke out between regime troops and armed rebels, the monitoring group added.
What started out as a popular uprising has over time developed into an increasingly militarised revolt, after President Bashar al-Assad's regime used force to crack down on peaceful protesters across the country.
According to the Observatory, more than 12,000 people have been killed in Syria since the revolt broke out in March last year, most of them civilians.