•A method to detect two categories of pesticides in vegetables was developed.•An orthogonal array experimental design optimized the experiment condition.•QuEChERs with DLLME-SFO provided good recovery of the pesticides.•The method is more environmentally-friendly than traditional methods.•The method was applied successfully to analyze pesticide residues in real samples. A simple, sensitive and environmentally-friendly method for determining organophosphorus and pyrethroid pesticides in vegetables was developed to better evaluate the risk of consuming them. The pesticides in vegetables were extracted, purified and concentrated by using the QuEChERS (quick, easy, cheap, effective, rugged and safe method) combined DLLME-SFO (dispersive liquid–liquid microextraction based on solidification of floating organic droplet) techniques. The key parameters were optimized through orthogonal array experimental design and statistical analysis. The linearity of the calibration curves was satisfied in matrix-matched standard solution with R2 ≥ 0.99. The limits of detection and limits of quantification were 0.3–1.5 and 0.9–4.7 μg/kg, respectively. The average recoveries of pesticides were 61.6–119.4% with relative standard deviations <16.1%. Furthermore, the method was applied successfully to analyse the pesticides in 15 pairs of organic and conventional vegetables. These results reflect the efficiency, reliability and robustness of the developed method.