When Poland acceded to the European Union, the Polish food legislation had to be matched up with the legal regulations of EU. In this paper, the authors attempt to determine the impact of harmonizing the food regulations on the decisions to be made by Polish food plants whether or not to implement systems that ensure health safety of food manufactured by them. The authors investigated and evaluated the progress made in implementing the HACCP system in the Polish food manufacturing plants. The plants under investigation and evaluation were from various food branches and of different sizes (big, medium, and small ones). A random sample of 150 production plants was surveyed by polling. Right now, the Polish food manufacturing plants are poorly prepared to manufacture health safe and quality food, and the preparation level is assessed as below 50%. However, the present situation is better than in the year 2000, and it continuously improves. A quick increase can be expected in the number of plants implementing and applying the principles of the HACCP system. The data obtained from the surveys in 2000 and 2003 show that, now, the number of food manufacturing plants with the HACCP system implemented plus plants starting to implement this system is twice as big as it was in 2000. This improvement results not only from the EU access. The food manufacturers declare their motivation and readiness to improve quality and health safety of the products they offer, and this fact is of the highest importance when winning new customers and business partners, both in Poland and in EU. Other vital reasons why the HACCP system is implemented are: lifting the customs barriers and a better and easier access to the highly demanding EU market.