Abstract: At present, there are many problems in the nail-fold microcirculation detection devices, such as huge structure, inconvenience to carry. In addition, due to the patient's body shaking, the video is difficult to keep stable in collecting with the device, which brings great difficulties to the doctor's observation. We develop a small image acquisition device for nail-fold microcirculation based on the principle of SDF imaging principle and liquid lenses technology. An annular lighting device is fixed in front of the optical system, and the overall design of the system is based on the characteristics of human fingers. The device is small, easy to carry and conform to the fingertips. It can focus quickly through a controller. It can also achieve high quality images of the nail-fold microcirculation. This study can promote the usage of nail-fold microcirculation device at the bedside. It's an efficient tool for medical workers to observe the microcirculation of patients.