The invention provides a sub-wavelength imaging device based on silicon balls and a photonic crystal negative refraction effect. The device comprises the silicon balls which are longitudinally arranged and a photonic crystal; the silicon balls are placed under the bottom edge of the photonic crystal; a light source is placed below the silicon balls; light output by the light source is incident onthe lower surfaces of the silicon balls, through one-time sub-wavelength imaging of the silicon balls, sub-wavelength focusing light spots are formed on the upper surfaces of the silicon balls, the sub-wavelength focusing light spots diffuse outwards, and after being subjected to negative refraction from the bottom edge and the bevel edge of the photonic crystal in sequence, negative refraction light beams are converged to one point outside the bevel edge of the photonic crystal to form a sub-wavelength imaging point. According to the sub-wavelength imaging device based on the silicon balls and the photonic crystal negative refraction effect, mainly, by means of parameter settings of the photonic crystal and the silicon balls, sub-wavelength imaging with half width smaller than 0.3 lambadacan be obtained; the whole device is small in size, after the device is fixed, in a whole imaging process, no parameter settings need to be adjusted manually, operation is simple, and the performanceis stable and reliable.