The magnetic characterirtics and ferromagnetic resonance linewidth of garnet system {Gdz-Y3-2x-zCa2X}[Fe2-ylny](Fe3-xVx)O12 was investigated as function of x, y, and z. 4 π Ms temperature stability depends on Tmax strongly. Putting Tmax to around 20C, 4 π Ms temperature coefficient α will be as low as 0.05% / °C. In this system, ferromagnetic resonance linewidth Δ H is very low and, Δ H is found to be composed with Δ Hint 0.2 Oe, Δ Hrelax 2.7⋅Z⋅Oe, and Δ Hani 0-30 Oe.It is shown that some combinations of x, y, and z displayed higher stability of 4 7r Ms temperature change and resulted in very low ferromagnetic resonance linewidth .