This study aimed at developing a valid and reliable instrument for measuring attitudes of primary schoolteachers toward inappropriate student behaviour. A systematic approach was used to develop the scale. Results provide preliminary evidence that the new instrument (consisting of 13 items on a six-point Likert type scale) meets the standards for reliability. Factor analysis with varimax rotation identified two distinct factors: (1) unproductive behaviour, and (2) aggressive behaviour. The alpha reliability coefficient was found to be 0.91 for the total scale, and 0.92 and 0.75 for first and second subscales respectively. The factor structure was tested using confirmatory factor analysis (CFA), which revealed that with a little modification, the identified model had a good fit for the data as all the key fit indices demonstrate highly accepted values including Goodness-of-Fit Index (GFI)>.95, Comparative Fit Index (CFI)>.96, and Root Mean Error of Approximation (RMSEA)< .05.