In 2012, released "has been two road people", "one day grass blue even sky" and other cover songs; the same year, to participate in zhejiang satellite TV "I love to remember the lyrics of the song" program recording, and sang live "love like tide". In December 2014, attended the "Silk Road Tingzhou Music Festival" press conference, and sang "Mom"; the same year, to participate in the "Silk Road Tingzhou Music Festival" held in Changji, Xinjiang; in the same year, Zhang Lei's video of him singing in a bar was put on the Internet by others. Afterwards, he was discovered by the film crew of "The Voice of China" and contacted by them.
On February 7, 2015, Zhang Lei held the first stop of his "Northern Border Tour"; in the same year, Zhang Lei took part in the competition of "The Voice of China Season 4" on Zhejiang Satellite Television, and during the blind audition, he got three mentors to turn around with a ballad song by Ma Di called "Nanshannan," joining Na Ying's team; on August 28 of the same year, he joined the B group of Na Ying on the "The Voice of China Season 4" on Zhejiang Satellite Television. The Voice Season 4" Na Ying group Battle battle, Zhang Lei and Zhu Qiang chorus "station", victory over opponents and enter the second round, the second round of singing "boat" and Sun Bolun showdown, and finally with Sun Bolun **** with the promotion of Na Ying group four, the top 16; August of the same year, with Sun Bolun, Changyu to participate in Tencent video "about the voice" seventh recording; the same year, the release of individual folk single "fairy mountain of the Moon"; September 18, the same year, zhejiang satellite television broadcast "the voice of China season 4" mix first 8 into 5, zhang lei and na ying, sunberlun, long yu, langga ram chorus of jay chou's "smoky flowers easy cold" as the opening song, and then sang the old wolf's "tiger's mouth" and li an PK, and ultimately 47:4 votes over the opponents to advance to the national top ten; in September of the same year, with li an, li xing ni, Chen Zitong, Sun Bolun to participate in Tencent video "about the voice" the tenth recording; September 30, the same year, zhejiang satellite television broadcast "the voice of China season 4" bird's nest sprint night 10 into 5, zhang lei sang jing gangshan's "loneliness is because of missing who", the comprehensive score of 94.6 points, and ultimately with the ranking of the first place in the ranking of the results of the national top five; in October of the same year, with tan xuan yuan, chen zitong, Bei Bei, Li An together to participate in Tencent video "about the voice" 12th recording; October 7, the same year, zhejiang satellite television live in the "voice of China season 4" finals, Zhang Lei and the top 48 trainees chorus "I love you China" as the opening song, in the first round of the chorus with na ying song "dream a + nanshannan", and then sang in the second round of the Li Jian's "stranger in a strange land" to get 11773 votes and become the champion candidate, in the third round of the chorus of the song "dream a + nanshannan", and then sing Li Jian's "stranger in a strange land" get 11773 votes and Become the champion candidate, in the third round of singing "travel" and Chen Zitong PK, and finally with 58.53% of the site support rate over Chen Zitong and won the national finals champion; October 8, the same year, attended the "The Voice of China Season 4" graduation ceremony held in Beijing, and accept the top ten music producer teacher issued a certificate of graduation; October 16, the same year, Zhejiang Satellite Television broadcast "The Voice of China Season 4" glory battle in the "The Voice of China Season 4", and accepted the certificate of graduation; October 16, Zhejiang TV broadcast "The Voice of China Season 4" glory battle in the "The Voice of China". The Voice of China Season 4" in the battle of glory, Zhang Lei sang "South Mountain South" and Zhou Shen, Li Wei PK, and ultimately to the team's total number of votes of 1,143 votes to win over their opponents; October 17 of the same year, to attend the "East China's first Tent Culture Festival and outdoor sports carnival around Chaohu Lake," and sang the "Tiger's Mouth," "Boat" and "South Mountain South" live. Boat", "Nanshannan" 3 songs; on October 31 of the same year, to help "The Voice of China Season 5" national auditions in Hefei District Huabang special field, and sang live "travel", "Tiger's Mouth" 2 songs; on November 10 of the same year, to participate in the "Jingdong 11.11" Jing "hi night --Large-scale competition song party", and sang the song "so you don't want anything"; in November of the same year, for the CCTV public welfare inspirational program "Speed Teenager" sang the theme song "young as the wind", and was awarded the CCTV Children's Channel "China's youth public welfare ambassador" medal. Youth Public Welfare Ambassador" medal; November 19 of the same year, launched a personal original single "Mom", the song by Mo Fan re-arranged; in December of the same year, to participate in the CCTV variety show "I want to go to the Spring Festival Gala", sang "Stranger in a Strange Land" successfully advanced to the "straight through the Spring Festival Gala" stage; on December 7 of the same year, the launch of the individual single "a thought of heaven", and as the theme song of the movie of the same name; on December 9 of the same year, the individual single "a thought of heaven", and as the theme song of the movie of the same name. Theme song; December 9 of the same year, launched a personal single "everything is fine", and as the theme song of the movie of the same name; December 12 of the same year, to participate in the "Rui Ci night China's good voice Shanghai Hongkou concert", and sang live "mother", "travel" 2 songs; December 17 of the same year, launched and the fourth quarter of the Voice On December 27 of the same year, he participated in the 2016 QQ Music "Best Time" New Year's Eve Concert held in Shenzhen, and sang "When You're Old", "Mom" and other songs on the spot; on December 29 of the same year, he released his personal single, "Knowing the Heart Through Warmth", which was included in the "The Voice of the Fourth Quarter". The student album - Na Ying group" compilation album .
In January 2016, to participate in the CCTV "through the Spring Festival Gala" competition, and ultimately failed to obtain the invitation to the Spring Festival Gala; in February of the same year, the launch of the individual single "Don't come unharmed" of the special version of the New Year .