The title of the thesis is the ownership certificate accomlishment from the land trading to
implement the law assurance and protection in Sleman Regency of Yogyakarta. The problem
formulation of the thesis is whether the ownership certificate accomplisment on the land
trading is closery related with the law assurance and protection and to analyze the effort to
improve the law assuramce and protection in acquaring the ownership certificate on the land
acquired from the trade. The research was empirical legal one using qualitative analysis
method from which the conclusion was drawn using inductive reasoning method. The
respondents in the research involved the holders of the land ownership certificate
accomplishment gained from the land trade indicitaed that there had been the law assurance
and protection in Sleman Regency, Special Region of Yogyakarta. It was proven from the
fact that of 130 respondents were subjected to the law suit from other party. The content of
the law suit was the juducial data to which teh solution was coucluted without legition and
with ligition. The prevebtive and repressuive effort to implement the law assurance and
protection was to pay attention to the caution priciple and positive publication priciple.
Keyword : Land ownership, land regition, Certificate, law assurance and law protection.