Background:- The study was conducted at Cheffa dairy farm with the objective of estimating the effects of none-genetic factors on Age at First Service (AFS), Age at First Calving (AFC), Calving Interval (CI), Days Open (DO), Number of Service per Conception (NSC), Lactation Length (LL) and adjusted 305 days milk yield (305-dMY). A total of 2343 records were collected from 123 cows and 13 sires' progenies having greater than 93.75 % HF blood levels through the period from 1996 to 2014 for evaluation. Independent variables were birth year and season, calving year and season and parity while AFS, AFC, CI, DO, NSC, LL and 305-dMY were dependent variables. SAS Version 9.1 software used for data analysis. Results:- The results indicated that year of birth had highly significant (p<0.01) and significant (p<0.05) effect on AFS and AFC respectively. Year of calving had highly significant (p<0.01) effect on CI and 305-dMY and significant (p<0.05) effect on DO and NSC. Season of calving had significant (p<0.05) effect on CI and 305-dMY. Longest records of CI and highest records of 305-dMY were exhibited in short rain season while, shortest and lowest records of CI and 305-dMY were recorded in dry and long rain seasons respectively. Parity had highly significant (p<0.01) effect on CI, DO, NSC and 305-dMY and significant (p<0.05) effect on LL. Longest value of CI, DO and LL were observed in 1st parity and highest value of NSC and highest value of 305-dMY were recorded in 7th and 5th parity respectively. The shortest value of CI, DO, LL and lowest value of 305-dMY was recorded in 9th parity while shortest value of NSC was recorded in 1st parity. Conclusions:- This study revealed, genetic performance of dairy breed in the study area was influenced by environment but selecting adapted animal from the herd and better management may improve all aspect of productivity. Hence, well record keeping, better management practice, non-genetic performance evaluation of economically important dairy traits and investigation of selection index were a prerequisite to improvement productivity of the herd and to run profitable dairy enterprise.