Judicial notice is a legal doctrine which is commonly used in countries, including the U.S., using the Common Law legal system and the accusatorial trial system as an exception of the principle of evidence law requiring deciding factual matters with evidence presented by the parties in the case. This doctrine is to cut off unnecessary evidential trials in the court since the considered fact is already notoriously known in the society or undisputable and to prevent the court from deciding a factual problem contrasting to the fact accepted in the society. In the U.S. which provides this doctrine in Federal Rules of Evidence, Rule 201, and in evidence codes of each state, similar to FRE Rule 201, federal and state courts have employed this provision to authorize searching and using Internet sources as a source of a fact noticed in cases for many years. Although some academics and judges in the U.S. disagree, this phenomenon is occurring and growing continuously. The majority of the U.S. jurists accept that the courts are competent to do so, but they suggest the courts must exercise due care in choosing the Internet sources. Their reliability must be unquestionable as Rule 201 demands only. Moreover, they also recommend the courts to examine the sources authenticity and modification of the information. From the comparative study between the U.S. law and Thai law, conditions, scope, and precedent of Thai courts regarding the Civil Procedure Code Section 84 (1) are substantially similar to Rule 201 of the U.S. To clarify, i.e., allowing the court to acknowledge notoriously-known facts from referencing sources highly reliable accepted by people in the society in general. Additionally, this article suggests applying the elements recommended by the U.S. scholars since the structure and characteristics of Internet between the U.S. and Thailand are essentially close. Finally, Thailand should amend CPC section 84 (1) by adding details, conditions and procedural measures to guarantee the right to a fair trial of the parties. Moreover, the article recommends issuing the trial rule of the President of the Supreme Court concerning authenticating the attributor of contents on primarily presumed-reliable Internet sources.