He initially became prominent during Emperor Yuan of Liang's campaign against the rebel general Hou Jing, and later, after Emperor Yuan was defeated and killed by Western Wei forces in 554, he maintained a separate center of power from the dominant general of the remaining Liang provinces, Chen Baxian.
The first historical reference to Wang Lin's military activities was in 549, when Xiao Yi, then governor of the important Jing Province (荊州, modern western Hubei), trying to send food supplies to the provincial armies trying to lift the siege on the capital Jiankang by the rebel general Hou Jing, ordered Wang to escort a large supply of rice to Jiankang's vicinity.
Fearful that the supply would be seized by Hou, Wang dumped the rice into the Yangtze River and returned to Jing Province.
In 551, Hou launched a major assault on Xiao Yi's territory, commanded by himself and his generals Ren Yue (任約) and Song Zixian (宋子仙), and after Hou made a surprise attack on Jiangxia (江夏, in modern Wuhan, Hubei) and captured it, he headed toward Xiao Yi's headquarters at Jiangling.
Xiao Yi thereafter made Wang Lin the governor of Xiang Province (湘州, modern central Hunan) and ordered him to first report to Jiangling to see him.
Wang Lin, realizing that something unusual was happening, sent his army directly to Xiang Province, commanded by his officer Lu Na (陸納), while personally reporting to Jiangling.
Meanwhile, Lu Na continued his campaign of resistance, hoping to force Emperor Yuan to free Wang Lin.
However, his subsequent attack on Baling was repelled by Emperor Yuan's cousin Xiao Xun (蕭循) the Marquess of Yifeng.
Meanwhile, Xiao Ji's forces were approaching Jiangling, and Emperor Yuan, wanting to pull Wang Sengbian's forces to resist Xiao Ji but feared that he would then lose control over Lu, sent Wang Lin to the frontline to have him to persuade Lu to surrender.
Eventually, Emperor Yuan agreed, pardoning Wang Lin and putting him back in charge of his original forces.
Meanwhile, Emperor Yuan, while having pardoned Wang Lin, still was apprehensive about the strength of his forces and his rapport with them, made him the governor of Guang Province (廣州, modern central Guangdong), against Wang Lin's wishes to guard Liang's northern borders with Western Wei in spring 554.
In fall 554, while Wang Lin was still on the way to Guang Province, Western Wei launched a major attack on Jiangling (which Emperor Yuan had made capital).
Meanwhile, also not recognizing Emperor Xuan was Wang Sengbian, who was then at Jiankang and who, along with his lieutenant Chen Baxian, controlled the eastern provinces.
He also continued fighting with both Western Wei and Emperor Xuan, but after Hou Ping rebelled against him in 556, he felt he was unable to conduct war on all sides.
He made nominal submissions to Northern Qi, Western Wei, and Emperor Xuan, suing for peace on all sides.
He also sought the return of his wife Lady Cai and heir apparent Wang Yi (王毅), who had been taken captive by Western Wei when Jiangling fell.
His subsequent campaigns to take over the modern Jiangxi region, however, were indecisive, preventing him from making a decisive attack on Chen.
He left his lieutenant Sun Yang (孫瑒) in command at Jiangxia, while he advanced east on the Yangtze River, heading toward Jiankang, with support from the Northern Qi general Murong Yan (慕容儼).
Meanwhile, Northern Zhou, the successor state to Western Wei, had heard of Wang's advances and launched an attack on Jiangxia.
Wang considered retreating, but decided to continue, hoping to get a decisive victory over Chen forces and then return to lift the siege on Jiangxia.
After this incident, Emperor Xiaozhao made him the governor of Yang Province (揚州, modern central Anhui), to defend Shouyang.