Abstract: To analyze the effects of puffing parameters on emissions in mainstream aerosols of electrically heated tobacco products, two commercial heated tobacco products (iQOS and GLO) were used as the test samples, and the contents of nicotine and WHO priority toxicants (carbon monoxide, formaldehyde, acetaldehyde, acrolein, NNN, NNK and benzene) in mainstream aerosols were measured under different puffing parameters. The results showed that:1) With the increase of puffing interval from 30 s to 60 s, the releases of carbon monoxide, formaldehyde, acetaldehyde and acrolein per stick decreased. 2) The releases of formaldehyde, NNN and NNK per unit nicotine generated by GLO were higher than those generated by iQOS. 3) Puffing parameters significantly affected the releases of nicotine, carbon monoxide, formaldehyde, acetaldehyde, acrolein, BaP, NNN, NNK and benzene of iQOS and the releases of carbon monoxide and acetaldehyde of GLO. 4) Puffing interval was the dominant influencing factor for iQOS.