Objective  To study the effects of the treatment with folic acid on intracellular folic acid levels of precancerous condition of gastric cancer.Methods  Gastric biopsy specimens were taken by endoscopy from 38 pantients with precancerous condition of gastric cancer(consisting of 18 patientis with gastric mucosa metaplasia of colon type and 20 patients with light or middle degree gastric hyperplasia),and verified by pathology.Intracellular folic acid level in these kinds of tissues was measured by the immulite automated immunoassay system and folic acid kid manufactured by DPC(Diagnostic products corporation)in USA.These patients were randomly divided into two groups,the trial group and the control group.the former were treated with folic acid 10?mg each time,three times a day for 3 months and the later were treated with sucralfate 1.0?g each time,three times a day for 3 months.The intracellular folic acid level was reexamined after therapy.Results  The intracellular folic acid level of trial group was higher after therapy than before therapy(  P  <0.05).There was no difference of intracellular folic acid level after therapy and before therapy in control group(  P  >0.05).Conclusion  The treatment with folic acid can rise intracellular folic acid level of precancerous condition of gastric cancer.