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Human immunodeficiency virus type 1 (HIV-1) recombinants in the world are believed to be generated through recombination between distinct HIV-1 strains among coinfection or superinfection cases. However, direct evidence to support transmission of HIV-1 recombinants from a coinfected/superinfected donor to putative recipient is lacking. Here, we report on the origin and evolutionary relationship between a set of recombinants from a CRF01_AE/CRF07_BC superinfected putative donor and diverse CRF01_AE/CRF07_BC recombinants from five putative recipients. Interviews on sociodemographic characteristics and sexual behaviors for these six HIV-1-infected men who have sex with men showed that they had similar ways of partner seeking: online dating sites and social circles. Phylogenetic and recombination analyses demonstrated that the near-full-length genome sequences from six patients formed a monophyletic cluster different from known HIV-1 genotypes in maximum likelihood phylogenetic trees, were all composed of CRF01_AE and CRF07_BC fragments with two common breakpoints on env, and shared 4–7 four breakpoints with each other. Moreover, 3' half-genomes of recombinant strains from five recipients had identical/similar recombinant structures with strains at longitudinal samples from the superinfected donor. Recombinants from the donor were paraphyletic, whereas five recipients were monophyletic or polyphyletic in the maximum clade credibility tree. Bayesian analyses confirmed that the estimated time to the most recent common ancestor (tMRCA) of CRF01_AE and CRF07_BC strains of the donor was 2009.2 and 2010.7, respectively, and all were earlier than the emergence of recombinants from five recipients. Our results demonstrated that the closely related unique recombination forms of HIV-1 might be the descendent of a series of recombinants generated gradually in a superinfected patient. This finding highlights the importance of early initiation of antiretroviral therapy as well as tracing and testing of partners in patients with multiple HIV-1 infection. Author summary: Recombination is a major mechanism for rapid evolution and diversification of human immunodeficiency virus type 1 (HIV-1). Multiple HIV-1 infection is believed to be a prerequisite for generating new recombinant strains. Recombinants sharing some breakpoints might have a common ancestor or direct parental/progenitor relationship or be irrelevant in evolution. However, evidence to support transmission of HIV-1 recombinants from coinfected/superinfected donor to putative recipients with recombinant descendants is lacking. Here, we report on a set of HIV-1 CRF01_AE/CRF07_BC unique recombination forms (URFs) from six HIV-1-infected men who have sex with men (MSM) in China with similar recombination structures and homologous parental strains. Moreover, the 3' half-genomes of all recombinants from five recipients had similar or identical forms with earlier continuous samples of a superinfected donor, and presented paraphyletic-monophyletic or paraphyletic-polyphyletic relationships in maximum clade credibility trees. These data suggest that HIV-1 superinfection might be a potential source of transmission of a series of closely related HIV-1 CRF01_AE/CRF07_BC URFs. Our study emphasizes the importance of continuous surveillance and early initiation of antiretroviral therapy in HIV-1-superinfected individuals with active high-risk behavior and substance abuse to prevent the generation and spread of recombinant strains among HIV-infected individuals. [ABSTRACT FROM AUTHOR]