Introduction: Among the three phases of clinical chemistry laboratory i.e. pre-analytical, analytical and post-analytical, it is the pre-analytical phase which contributes to most of the errors. Pre-analytical phase includes completion of laboratory requisition form, phlebotomy, specimen identification, sample handling and transportation to the laboratory. From various pre-analytical errors, the errors related to sample collection are very high. This study was undertaken to completely assess the sampling errors in a tertiary care teaching hospital. Material and Methods: The study was undertaken to access the sampling errors in a biochemistry laboratory of a tertiary care hospital. It was a prospective study. Following quality indicators were assessed in the study i.e. inappropriate container, hemolysed sample, insufficient sample volume, damage to the container, improperly labeled sample and mismatch sample. Results: Out of total 972 samples the maximum percentage of error was seen due to improperly labeled sample accounting to 1.23%, this is followed by hemolysed sample accounting to 1.03%. Conclusion: Our study shows that there is need to understand the importance of pre-analytical phase with special emphasis on the sample collection related errors. Sensitizing the healthcare professionals about the errors related to sample collection reduces the overall percentage of errors which has a positive impact on the health outcome of the patients.