To investigate the relationship between socs3 mRNA expression and jak2v617f point mutation in bcr-abl negative patients with myelo-proliferative disease (MPD), 62 bcr-abl negative MPD patients (26 cases of PV, 26 cases of ET, 9 cases of IMF, and one case of CNL) were arranged as experiment group, and the others (20 cases of CML, 10 cases of AL and 15 healthy volunteers) were arranged as control group. All the diagnosis had been made according to the 2001 WHO criteria. jak2v617f point mutation was detected by AS-PCR and confirmed by direct sequencing. The expression level of socs3 mRNA was measured by RT-PCR. The association jak2v617f point mutation with socs3 mRNA expression in bcr-abl negative MPD patients was observed and analyzed. The results showed that among 62 bcr-abl negative MPD patients, the somatic jak2v617f point mutation was positive in 44 patients (PV 23, ET 15, IMF 5, CNL 1) while negative in the other 18 patients and control group. The expression of socs3 mRNA could be detected in 39 patients from 44 jak2v617f mutation positive patients and in 10 patients from 18 jak2v617f mutation-negative patients. There was a statistically significant difference in socs3 mRNA expression rates between jak2v617f mutation positive and negative group (chi(2) = 8.44, p < 0.005). There was a statistically significant difference in socs3 mRNA expression levels between jak2v617f mutation positive and negative groups (p = 0.035). It is concluded that there is a statistically significant difference in the expression level of socs3 mRNA in the patients between jak2v617f mutation positive group and negative group.