Time-resolved soft X-ray spectra measurement has been deveoped for studying laser-produced plasmas by using a gold transmission grating (TG) coupled to a soft X-ray streak camera. Recently we fabricated the TG with a line density of about 8531/mm on a substrate of a 0.5 micron thick polyimide membrane. Timeresolved spectra of gold (20μm in thickness) planar targets were abtained. The planar targets were irradiated with 680 ps laser pulses (λ=0.53μm) from the LF11# Nd: glass laser system. The emission intensity with temporal variation for O band from gold plasmas was observed.