Abstract: The porous aluminium coating inlaid with copper was obtained by implanting Cu into the pores of anodic oxidation aluminium coating prepared by electroplating. In order to study the influence of sample interval and slit width on the transmission spectra, the transmission spectra of porous aluminium coating with copper in the case of the same sample interval with different slit widths and the same slit width with different sample intervals were measured by UV3101 spectrophotometer respectively. Then the influence of sample interval and slit width on the transmission spectra was analyzed, and the suitable sample interval and slit width for measuring porous aluminium coating with copper were achieved. Experimental results indicate that the slit width of 3 nm and the sample interval of 0.5nm or 1nm are suitable for the visible waveband, and the slit width of 5nm or 8nm and the sample interval of 2nm are suitable for the nearIR waveband.