The study assessed the effect of low altitude and near sea level training on cardiopulmonary and electrolyte level of male amateur endurance runners of Bauchi State, Nigeria. Pankshin and Bauchi, which are located at altitudes of 1414 m and 628 m above sea level respectively were used as low altitude and near sea level centres for this study. Repeated-measures experimental research design was used for the study. Training was conducted in two different environments (low-altitude and near sea-level) with seven assessments (base-line, immediately after the first, second and third week of training at low-altitude and near sea-level) on seven variables (haematocrit, pulse rate, respiratory frequency, VO2max, potassium ion, sodium ion and speed endurance). Training was maintained between 60 - 85% of maximal heart rate of individual runner from Monday to Saturday for a duration of three (3) weeks on each location. The population for the study was twenty (20) male amateur endurance runners of Bauchi and a sample size of fifteen (15) male amateur endurance runners of Bauchi were drawn using purposive and simple random sampling techniques. All training sessions were conducted between 7:00am to 8:30am and 4:30 pm to 6:00 pm. The daily training programme included road walk (6 - 12) km, hill training and interval sprint training on a 400 m track. The participants‟ haematocrit, pulse rate, respiratory frequency VO2max, potassium, sodium and speed endurance were assessed at base-line, immediately after the first, second and third week of stay at each Centre. The descriptive statistics of mean and standard deviation were used to describe the data on the physical characteristics of the participants. The inferential statistics of repeated-measures analysis of variance and simple linear regression were used to test the hypotheses. An alpha-level of 0.05 was used to retain or reject the null hypotheses. The analysis of the results revealed that training at both low-altitude and near sea-level had statistical significant effect on pulse rate (p = 0.000); haematocrit level (p = 0.000); VO2max (P = 0.000) and speed endurance (p = 0.000) of amateur endurance runners of Bauchi State, Nigeria. Based on these findings, it was concluded that three weeks each of training at low altitude and near sea level reduced pulse rate, increase haematocrit counts, improved VO2max and improved speed endurance of male amateur endurance runners of Bauchi State, Nigeria. Thus, exposure to low-altitude and near sea-level training were shown to have improved the performance indices of male endurance athletes. Therefore, the researcher recommended that low-altitude and near sea-level training should be adopted as part of endurance runners training circle for optimal performance.