Re(CobalFe0.10Cu0.08Zr0.03)7.55(Re=Sm, Ho, Er) alloy ribbons were prepared by a melt-spun method. The effects of substitution of heavy rare-earth elements, Ho and Er, for Sm on the magnetic property of 2:17 type SmCo alloy were investigated. Results show that the (Sm0.5Ho0.5)(CobalFe0.10Cu0.08Zr0.03)7.55 sample exhibits an excellent magnetic property at room temperature with the Hci higher than 800 kA/m. The Hci of Sm(CobalFe0.10Cu0.08Zr0.03)7.55 alloy ribbon first decreases and then increases with the temperature increasing until 400 oC, and then presents a sharp decline. The Ms of Sm(CobalFe0.10Cu0.08Zr0.03)7.55 alloy ribbon decreases continually with increasing of the temperature. The Hci of (Sm0.5Ho0.5)(CobalFe0.10Cu0.08Zr0.03)7.55 sample decreases gradually with the temperature increasing, but its Ms increases with temperature increasing until 400 oC and then decreases. The Hci of (Sm0.5Ho0.5)(CobalFe0.10Cu0.08Zr0.03)7.55 sample is lower than that of the sample without Ho element above 250 oC, but its Ms is much higher than that of the sample without Ho element. Above 300 oC, the (Sm0.5Ho0.5)(CobalFe0.10Cu0.08Zr0.03)7.55 sample presents higher Ms. It indicates that optimized ratio of the substitution of Ho for Sm is one of the paths to obtain excellent high-temperature magnetic property