From 2007, studies have suggested a role of undercarboxylated osteocalcin (ucOC) in glucose metabolism. The aim of the study was to investigate the relationship of ucOC level and blood glucose (BG) control in newly diagnosed type 2 diabetes (t2D) and its change with BG control improvement. Fifty seven newly diagnosed t2D patients had a consultation about life style changes on visit 1 but no BG regulation medication. The final visit (2) was after three months. BG metabolism and bone turnover parameters were measured on visit 1 and 2. Thirty two patients reached the target HbA1c ( 7%). No correlation of ucOC and HbA1c and FBG was observed. Median HbA1c and FBG changed significantly (8.0 to 6.5%; 9.0 to 7.0 mmol/L resp.; Wilcoxon signed rank test p0.001), ucOC was slightly but not significantly lower (2.0 to 1.4 mcg/L; p=0.465). No correlation between differences in HbA1c and ucOC between Visits 1 and 2 was revealed. This study failed to prove the relationship between BG regulation and ucOC level. However, it does not exclude it, so further research is needed. The fact that as much as 56% patients achieved the target HbA1c with no medication, challenges most BG control guidelines.