A plough-type fertilizer device, ditching the furrow with plough-type surface and fertilizing through the middle of plough leg, was designed to operate with rotary tillage unit of rapeseed direct planter and to realize positive deep fertilization function, which can improve the fertilizer utilization ratio and passing performance. The plough-type surface, plough leg and plough side plate were designed and the structure parameters of soil breaking surface and soil guide plane were determined. The relationship between forward speed and fertilizer depth, depth of ditch after soil covering were analyzed by numerical soil bin experiment. The results showed that qualification rate and stability coefficient of fertilizer depth were 95% and more than 90.37%, respectively. The forward speed was 1.1 km/h, 2.2 km/h, and 3.3 km/h, respectively. The plough-type fertilizers were assembled into rapeseed direct planter and the field test was carried out. The result showed that qualification rate of fertilizer depth was 94%. The stability coefficients of different line were 96.87%. The rapeseed root at the stage of flowering, output with drilling mixed fertilization, and vertically deep fertilization treatments were analyzed. The result showed that rapeseed root at the stage of flowering and output from deep fertilization by plough-type fertilizer device was improved.