The research aims to study the factors affecting construction cost in construction projects. A questionnaire form include factors which affects construction cost, like environmental factors, construction parties' related factors, construction items related factors, cost estimating factors and financing factors. The questionnaire form survey includes 38 factors and different columns of degree of severity. The survey form was filled up by contractors (10), consultant (5) and owner (5) according to their experience of construction work. The form was distributed to 30 participants. The severity index was calculated for all 38 factors to provide ranking according to contractor, consultant and owner/client. The top ten factors were consider according to participants which affects more and whose severity index is also high comparison to other factors are cost of materials, incorrect planning, previous experience of contract, contract management and poor financial control on sites. The spearman's, Kendall correlation and rank agreement factors were calculated to see the correlation between contractors, consultants and owners/clients views.