The arrest of local resident Feng Zhijun, 41, comes a day ahead of a key meeting of top leaders of the party here to discuss new set of reforms to halt the slowdown of the Chinese economy and to reform the country's social security system amid rising concerns over increasing gap between rich and poor.
The suspect admitted to the crime after his capture in the early hours, state-run Xinhua news agency reported, quoting local police as saying.
Feng has previously served nine years in prison for theft, police said, adding investigations are on.
Police did not reveal Feng's motive in carrying out the bomb attack at the highly guarded CPC office.
More From This Section
The November 6 explosions were caused by self-made bombs in front of the sprawling Shanxi Provincial headquarters of the CPC and killed one person besides injuring eight others, including one seriously.
His arrest, however, sets at rest earlier speculation that the attack could have been caused by Islamic militants from Xinjiang as the incident took place close on the heels of the October 28 car crash at Tiananmen square in which five persons were killed and 40 others injured.
In 2011, a farmer from the same province, who was aggrieved over the demolition of his property, detonated three self-made bombs in front of Communist Party offices in Fuzhou in southern Jiangxi province.
Two persons were killed and six others were injured in the incident.
A person, who became paralysed in police brutality, set off explosives at the airport in July to highlight his plight.
Earlier, another disgruntled man set himself on fire in Xiamen city, killing himself and 46 others.
China also witnessed numerous knife attacks by disgruntled people.