Yes. To name just two examples, the PRC invaded Tibet in 1951, as discussed by /u/JimeDorje in this answer, and Vietnam in 1979, as discussed by /u/hellcatfighter in this answer. Of course, there have been other historic cases of states we might call 'China' undertaking expansionist action, most dramatically in the Qing wars of expansion which I cover here, and we can also speak of Chinese colonialism at various points, as I do here.

Every nation will usually frame its wars as defensive or humanitarian. They will say "These are the acts our enemies have done and that is why they are the aggressor that we must defend against." To assign a label of aggressor we must evaluate whether the stated provocations actually exist and make a subjective call on whether the military action undertaken is an appropriate and proportionate response. Sometimes a justification for war can be a real grievance but is clearly (at least in our judgement) just an excuse for something the aggressor nation wanted to do anyway.

Here are some wars that the People's Republic of China has been involved in. Not all the linked answers will directly address your question, but they will help point you in the right direction.

Tibet (1950s - present)

This would be an especially controversial one in China, because the position of the CCP is that the incorporation of Tibet into the PRC was not a foreign conquest but the return of a rebellious territory that formed an integral part of China's natural borders. Many Tibetans would feel different.

u/randomguy0101001 answers Did the Chinese Communist takeover of Tibet free the peasant class from the tyranny of Feudal lords?

u/EnclavedMicrostate and u/hellcatfighter answer Why does China think it owns Tibet and/or Taiwan?

Korean War (1950-53)

The PRC entered the war to defend North Korea, who had started the war by invading South Korea.

u/schloopy12 answers [What were some of the reasons why China ended up invading Korea to start the Korean War?] (https://www.reddit.com/r/AskHistorians/comments/ev98nt/what_were_some_of_the_reasons_why_china_ended_up/)

u/rmacdowe answers Considering that the US was still the only nuclear power at the time, what led to China's willingness to contribute men and materiel to North Korea during the Korean War? Were they never worried that men like MacArthur would get their way and launch a nuclear war in retaliation?

Sino-Indian War (1962)

u/drylaw answers The Sino-Indian War of 1962 is perceived in India as being almost entirely a result of Chinese aggression and infiltration into the region of Aksai Chin. To what extent is that narrative accurate?

Sino-Vietnamese War (1979)

u/hellcatfighter answers China smashed through northern Vietnam during the 1979 Sino-Vietnamese war, but then just withdrew. Why didn't they push on or negotiate to get a concession?

u/hellcatfighter answers How strictly were the three rules of discipline and eight points of attention followed by the red army and PLA during the Chinese civil war, Korean war and sino Vietnamese war/skirmish?

u/hellcatfighter answers Why did the Sino-Vietnamese split happen later than the Sino-Soviet split? Was there any unwillingness to support the North Vietnam in the Vietnam war in the late 1960s, given that Vietnam was firmly in the Soviet camp?