Rationale and Background: Risk factors associated with Type 2 diabetes mellitus (DM) may differ between population groups and ethnicities. In Lao PDR (Laos), no studies have been conducted to investigate the potential risk factors for Type 2 DM. Methodology: A case-control study was conducted among 150 patients with Type 2 DM who were matched for age and sex with 300 patients presenting at OPD with non-DM diseases, at Setthathirath Hospital between November 30, 2007 and April 30, 2008. Results: Most of the study patients (97.5%) were Lao Loom with an overall mean (95%CI) age of 57.6 (56.6- 58.5) years. The mean (95%CI) daily expense (Lao Kip) was significantly higher in cases [38,700 (35,213- 42,186)] compared to controls [31,400 (29,667-33,132)] (P<0.001). The median (range) number of bottles or cans or glasses of sweet soft drink drunk by the study subjects per week (Pepsi or fruit juice or sugar cane juice) were significantly higher in the cases compared to the controls (P<0.001). Although the proportion of the patients who previously drank alcohol was similar between two groups, the mean (95%CI) number of glasses of whisky drunk by the patients per week was significantly higher in the cases [4.1 (2.8-5.4)] compared to the controls [1.8 (1.4-2.3)] (P<0.001). The percentage of patients with history of cigarette smoking and the mean (95%CI) number of cigarettes smoked per day were not significantly different between the groups (P>0.05). Although the frequency of the patients who did regular physical exercise was not statistically different between the cases (31%) and the controls (27%) (P=0.48), the mean (95%CI) body mass index was significantly higher in the cases [28.3 (27.7-28.9)] compared with the controls [24.9 (24.5-25.4)] (P<0.001). A history of family members with DM was significantly higher among the type 2 DM cases (31%) compared with the controls (16%) (P<0.001), [OR= 2.3; 95%CI = 1.4 - 3.7)]. The history of NSAID/Steroid and traditional-herbal use was associated with type 2 DM [OR = 2.6; 95%CI = 1.3 - 5.0) and OR = 2.7; 95%CI = 1.7 - 4.6), respectively]. Conclusion: Higher expenditure, sweet soft drink consumption, BMI, a history of family members with DM, and history of NSAID/steroid or traditional herb use were risk factors associated with type II DM among Lao patients. Further studies are required in order to confirm the findings of this study especially in different hospitals and parts of Laos. Copyright: ! 2012 Xaysanavong et al. This is an open-access article distributed under the terms of the Creative Commons Attribution Licence, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.