Our aim was to study the influence of the surface treatment process on the mechanical properties of an adhesive. This study takes aluminum alloy 6061 as the substrate; carries out grinding, sandblasting, plasma, grinding + plasma, and sandblasting + plasma surface treatment processes; and chooses the ISR 7008 adhesive to make aluminum alloy butt joints, and the joints Connectors are in −40 °C, −20 °C, 0 °C, 40 °C, 60 °C, and 80 °C environments, respectively (1–3 days of a constant-temperature test). The results show that the plasma surface treatment process helps to improve the activity and hydrophilicity of the bonding surface; the plasma surface treatment process helps to improve the adhesive strength of the joints under the environment of −40 °C and 80 °C; and under the environment of −20–60 °C, the sandblasting + plasma surface treatment process helps to improve the adhesive strength of the joints. By analyzing the infrared spectra of the ISR 7008 adhesive, it was found that the contents of ${\gamma }_{\mathrm{N}-\mathrm{H}}$, ${\nu }_{\mathrm{C}-\mathrm{C}}$, ${\nu }_{\mathrm{C}-\mathrm{N}}$, and ${\nu }_{\mathrm{C}-\mathrm{O}}$ were higher in the interval from 25 °C to 80 °C than those in the interval from −40 °C to 0 °C, which resulted in the decrease in adhesive properties.