Finland has undergone a total reform of its Penal Code since the beginning of the 1970s. The reform first started with the work of the Criminal Law Committee，which carefully pondered the foundations of the reform and the basic principles and commitments that were to form the basis of the actual reform. The reform work continued with the work of the Criminal Law Project，the task of which was to continue the work of the Criminal Law Committee and actually draft the new provisions forming the future Penal Code of Finland. The reform was officially completed in 1999，but actually it is，however，not complete even today. Criminal Law Committee and Criminal Law Project based the total reform of the Finnish Penal Code on certain principles. These principles illustrate the very design of Finnish criminal law and criminal justice policy. These principles also illustrate that the total reform of the Finnish Penal Code has not been carried out without a vision on the functions and objectives of criminal law and criminal justice policy. Instead，quite of an amount of time has been consumed in formulating these principles. This has，however，perhaps led to a situation where single substantive penal provisions have not been so carefully designed. The main purpose of the article is to carefully elaborate these principles that formed the foundation of the total reform of the Finnish Penal Code and the function of each principle. In

addition，a wider perspective is also adopted. The principles formulated illustrate also the close connection of criminal justice policy and criminal legislation in Finland while the principles are explicitly affiliated with the objectives of the Finnish criminal justice policy. Also constitutional connections of the principles，such as connections to legal certainty，are examined.