Objective To explore the effect of different pipetting manual on the accuracy of adjustable micropipette. Methods The adjustable micropipette with different ranges was used to deliver blood serum, water, isopropanol and anhydrous ethanol. The effect on the accuracy of pipetting was estimated at different conditions, such as the range adjusting, style of tip fixing, with or without tip pre-soaking, pre-soaking time, and angle of soaking, pipetting velocity and pipetting depth. Results The accuracy of adjustable micropipette was significantly increased when the target volume was close to the maximum range of pipette. In addition, vertical tip fixing, pre-soaking tip 2 to 3 times, deeply and perpendicular soak for about 3 seconds, slowly pipetting also increased the pipetting accuracy significantly. Most notably, that over-rotating the scale before setting to the target volume shows the best effect on improving the pipetting accuracy. Conclusion Good practice of adjustable micropipette could improve the experimental accuracy.