The research was conducted in the years 1999–2001 on a special field experiment at the Experimental Station in Osiny in which different crop production systems are compared. Two systems were compared: conventional (pulse crops, winter wheat, triticale + intercrop) and integrated (potato, spring barley, pulse crops, winter wheat + straw + intercrop). The experiment was established with no replication and with all fields cultivated at the same time. The area of each field in both systems was about 1 ha, which made this experiment more similar to standard agricultural conditions in Poland. In the conventional system faba bean cultivated after winter triticale and stubble crop yielded on the level of 3.3 t/ ha. This yield was on average 17% higher than in the integrated system. It was due to a better forecrop in the conventional system and it was the most important factor influencing different morphological features of faba bean. In this system intensive application of chemical plant protection against diseases and pests affected weaker infestation of plants by fungal diseases responsible for Botrytis fabae Sard. and Botrytis cinerea Pers. More effective protection against this kind of diseases made the yields and other elements of yield structure (e.g. number of pods, plant density, seed weight per plant and seed size) of faba bean better.