Abstract: In order to study the effect of organic-inorganic fertilizer on nutrients absorption of the crops and improvement of soil fertility, pot experiment was to study the effects of application of organic-inorganic fertilizer on nutrient uptake and fertilizer use efficiency of lettuce. The results showed that: compared to chemical fertilizer application only, combined application of organic fertilizer (fine organic fertilizer and bio-organic fertilizer) and inorganic fertilizer contribution rate increased 6.4 and 6.8 percentage point. At the same nitrogen application level, compared to chemical fertilizer application only, combined application of refined organic fertilizer and inorganic fertilizer and combined application of bio-organic fertilizer and inorganic fertilizer (organic nitrogen: inorganic nitrogen=4:6) could increase the lettuce biomass significantly, promote the NPK nutrients absorption of the lettuce on, improve the nitrogen use efficiency. Combined organic (fine organic fertilizer and bio-organic fertilizer) and inorganic fertilizer application compared with single chemical fertilizer application, biomass increased by 38.7% and 41.6% ; lettuce nitrogen, phosphorus and potassium content increased by 12.9% and 17.5%, 7.0% and 12.8%, 7.3% and 17.2%, lettuce nitrogen use efficiency increased by 9.2% and 13.7%, respectively.