At age 9, Song Weilong developed an interest in classic martial arts after watching the action movie The New Legend of Shaolin starring Jet Li.

[16] In 2018, Song starred opposite Guan Xiaotong in the historical drama Untouchable Lovers;[17] as well as sci-fi adventure film Dream Breaker.

[25] On March 19, 2016, Song attended the "Green Bicycle Tour" charity event in Chengdu as its youth ambassador.

Song presented the Innisfree x Yongjiu crossover road bike collaboration and hosted the fan meeting afterwards.

[29] In September 2020, Song was appointed brand ambassador for British luxury fashion house Burberry after participating in its Trench Coat advertising campaign.

[30] In 2020, Italian luxury fashion house Emporio Armani announced that Song would serve as brand spokesperson for its Men's Watches in Greater China and the Asia-Pacific region.