The objective was to evaluate the efficacy and toxicity of leucovorin plus 5-fluorouracil combined with oxaliplatin (modified FOLFOX regimen) every 2 weeks on previously untreated advanced colorectal cancer patients in the Chinese population. Fifty-one inpatients were enrolled to receive 85 mg/m oxaliplatin intravenously over a 2- h period on day 1, together with 400 mg/m2 leucovorin over 2- h, followed by a 46-h infusion of 5-fluorouracil at 2600 mg/m2 every 2 weeks. Treatment was given until progression or unmanageable toxicity ensued. In all, 51 patients received three or more oxaliplatin doses and a median of nine treatment cycles (range 3-16 cycles). Of the 51 eligible patients, two complete responses and 22 partial responses were observed for an overall response rate of 47.0% (95% confidence interval 35-64%). Median progression-free survival was 7.7 months (95% confidence interval 6.8-8.6) and median overall survival was 15.0 months (95% confidence interval 13.1-16.9). Toxicities were mild: five patients (9.8%) reported grade 3-4 neutropenia, 33 patients (64.8%) experienced grade 1-3 neurotoxicity and only six patients (11.8%) experienced grade 3 neurotoxicity. The leucovorin plus 5-fluorouracil combined with oxaliplatin (modified FOLFOX) regimen is active and well tolerated in patients with previously untreated advanced colorectal cancer in the Chinese population.