For OCT imaging, enhancing contrast efficiency will lead to significant improvements in the detection limits in cancer. Recently, noble metal nanoparticles are considered to be better contrast agents than traditional ones, especially for gold and silver. Silver nanoparticles have more attractive optical properties than gold nanoparticles. But they are employed far less because of its poor chemical stability. In this paper, we introduced our recent progress on a new application of using gold/silver alloy nanoparticles as OCT contrast agents in the detection of ovarian cancer. The scattering properties and sensitivity of silver were investigated. By means of tuning LSPR wavelengths of the nanoparticles, they were able to match the central wavelength of light used in OCT. Before carrying out animal experiments, we evaluated the different performances of alloy nanoparticles and gold nanorods in vitro. It has been sufficiently demonstrated that the alloy nanoparticles revealed stronger OCT signals than gold nanorods because of the better scattering properties. Then in vivo study, we compared the contrast enhancement of gold/silver alloy nanoparticles and gold nanorods on the ovarian cancer model mice. This study contributes a new kind of contrast agent in OCT imaging, which has a profound effect on drug delivery and further therapeutic action.