The aim of this study was to identifythe investment status of non-financial firms in Vietnam. A
panel data of 184 non-financial companies listed on Hochiminh Stock Exchange was collected over the period
from the year 2013 to the year 2017. With the aim of assessing investment status, Richardson's theoretical
model of investment was adopted to separate irrational investment into over-investment and under-investment.
This studyemployedpanel data regression with the fixed effects model to find investment residual. Then, the
study combined the investment residual estimated from the research model and the Tobin's Q index to classify
firm investments into three groups as over-investment, under-investment and normal investment. Based on the
empirical findings, the study provided some policy implications for the corporate governance.