Li had previously been dismissed as defence minister and as a state councillor in October without any official explanation.
The leadership may want to use the gathering to focus on efforts to get the country’s economy back on track.
Qin was last seen in public when he met senior diplomats from Russia, Vietnam and Sri Lanka on June 25 last year.
He was ousted as foreign minister a month later, making his the shortest spell in the position. His disappearance had prompted intense speculation about his whereabouts after he missed a number of regional meetings and visits to China by senior foreign figures.
At present he is still a member of the 205-strong Communist Party Central Committee.
Qin’s predecessor Wang Yi, who had been appointed as the party’s foreign policy chief, resumed his former duties after the dismissal was confirmed.
The website of China’s defence ministry still listed Li as a member of the Communist Party’s Central Military Commission late last week, but it was not there on Tuesday.
The Central Military Commission is a parallel system for the party and the state, with the same membership. Li had already been removed from the state CMC in October.
Li is still a member of the party’s Central Committee and retains his seat in the legislature.
Last year also saw a number of senior generals being removed from their commands, prompting speculation that President Xi Jinping’s anti-corruption drive is deepening in the military.
Those affected include the leadership of the People’s Liberation Army Rocket Force who were responsible for the country’s nuclear arsenal.
The NPC this month said the nine were suspected of “violations of discipline and the law”, usually a euphemism for corruption.
New Defence Minister Dong Jun, a former head of the navy, has not yet been given the rank of state councillor or a seat on the CMC, something all previous defence ministers have received.
The Standing Committee also announced that a lieutenant general, Li Zhizhong had been dismissed from the legislature.
Li’s command roles included serving as deputy commander of the Central Theatre Command, head of the equipment department of the PLA ground force and chief of staff of the Southern Theatre Command’s ground force.
Additional reporting Amber Wang