A boot for a skate has a shoe frame and a shoe sheath. The shoe frame has a heel shank and an insole. The shoe sheath is mounted on the shoe frame and has a sidewall, an internal soft pad and a leather upper cover. The sidewall has an internal chamber. The internal soft pad is made of resilient material and has multiple air vents defined through the internal soft pad. The air vents improve the ventilation of the sidewall to make a sole of a foot inside the sidewall feel comfortable without sweating easily and also keep the sole from becoming unhealthy.