Abstract: The reliability of radiocarbon dating depends on the reliability of dating material. The wood material is considered most reliable for dating,but it isn't easy to get in the loess-paleosol sequence.Commonly dated material is organic matter, with the amount less than 2% in the sequence and affected by modern plant rootlets and agriculture,making younger ¹⁴C ages of all the organic materials but our laboratory can efficiently isolate young organic matter by adopting new pretreatment method. Our study shows that pollen may be a better material for dating paleosol in the condition that pollen was deposited simultaneously with sediment in the stable sedimentary environment.From a loess profile sequence dating terrestrial shells that may absorb different ¹⁴C concentrations from around environment will result in dates with low precision, and thus the shells with aragonite are generally chosen for dating. Combining the reliable dating material based on correct pretreatment with AMS method, we can acquire high resolution and reliable dating.