The official was the chief of staff of the centre and had been working for Russia's Federal Security Service (FSB), the SBU said on the Telegram messaging app.
It did not name him.
"We used encrypted software to get into his gadgets. We were constantly 'living' with him... And we managed to qualitatively document the collection and transmission of information to the enemy," SBU chief Vasyl Maliuk said.
The security service recorded at least 14 such episodes and detained the official for state treason, Maliuk said.
The official had worked in the Ukrainian security service since 2014 and was recruited by FSB in 2018 in Vienna, the SBU said.
He had not carried out active espionage activities before Russia's FSB re-established contact with him in December, the SBU said, adding it was tracking this communication.
Maliuk said the SBU had sent Russia misinformation during its operation in order to catch the suspected spy but did not provide details.
In the course of the nearly three-year full-scale war with Russia, Ukrainian officials have reported numerous operations to uncover agents recruited by Russian officials.
Ukraine has accused them of spying, supplying co-ordinates of military targets, setting fire to military vehicles and other malign activities.
The SBU said that Russia tasked its spy network, which the detained official was part of, with gathering data on Ukraine's awareness of Russia's frontline movement as well as on critical infrastructure and the aftermath of Russian deep strikes into Ukraine.
Information about military and political leadership and Ukraine's weaponry were matters of interest as well.
"The official worked for the enemy not only for ideological but also for financial reasons," Ukraine's SBU said.
The SBU has recently also accused Russian spies of orchestrating explosions in military draft offices across Ukraine in order to undermine the mobilisation effort.
The SBU, like the Russian domestic intelligence agency FSB, emerged from the Soviet-era KGB.
US Defense Secretary Pete Hegseth said on Wednesday that a return to Ukraine's pre-2014 borders was unrealistic.
Speaking at a meeting of Ukraine's allies at the headquarters of the NATO military alliance in Brussels, Hegseth delivered the clearest and bluntest public statement so far on the new US administration's approach to the nearly three-year-old war.
"We want, like you, a sovereign and prosperous Ukraine. But we must start by recognising that returning to Ukraine's pre-2014 borders is an unrealistic objective," Hegseth told the meeting of more than 40 countries allied to Ukraine.
"Chasing this illusionary goal will only prolong the war and cause more suffering," he added.
Russia annexed the Black Sea peninsula of Crimea from Ukraine in March 2014 and then backed pro-Russian separatists in an armed insurgency against Ukrainian forces in the eastern Donbas region.
Russia controls about 20 per cent of Ukraine's territory, mainly in the east and south.
Hegseth said any durable peace must include "robust security guarantees to ensure that the war will not begin again".
But, he said, "the United States does not believe that NATO membership for Ukraine is a realistic outcome of a negotiated settlement".
with DPA
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