The study investigated the "Relationship between test construction and administration skills’ on students’ achievement in Economics in senior secondary schools Abuja, Nigeria." It utilized a correlational survey research design, guided by three research questions and corresponding hypotheses. The population comprised 26,954 respondents, including 26,954 Economics students and 223 Economics teachers from 62 senior secondary schools in Abuja. The sample consisted of 436 respondents, comprising 379 SS II students and 57 Economics teachers, selected from three area councils of Abuja using a multistage sampling technique combined with simple random sampling. The researchers developed instruments for data collection namely: Economics Test Construction and Administration Skills Inventory (ETCOASI) and Economics Achievement Test (EAT), validated by two experts. EAT demonstrated a validity index of 0.88 and a reliability coefficient of 0.89 through content validity and the Kuder-Richardson 20 method. Meanwhile, ETCOASI exhibited a validity index of 0.68 with reliability coefficients of 0.77 using construct validity and Cronbach's Alpha methods. Data analysis involved descriptive statistics (mean and standard deviation) to address research questions and Pearson's Correlation Coefficient (r) for testing hypotheses at a significance level of 0.05. The findings underscored a significant relationship between effective test construction skills and student academic achievement in economics. Despite educators' subject matter expertise, opportunities exist to better align assessment with the cognitive demands of Economics achievement tests. Contextual factors such as educational background and participation in professional development programs were identified as significant relationships of economics teachers' test construction skills. The study recommends a comprehensive reassessment of current assessment practices to enrich students' Economics learning experiences in secondary education settings. It concludes with practical suggestions aimed at enhancing Economics assessment practices.