We contrastively analyzed pathogens and their drug sensibilities of lower-respiratory-tract infection in chronic pulmonary heart disease in two different periods. The results were that the Gram-positive cocci (GPC) was 43.8% and Gram-negative bacilli (GNB) was 56.2% in Group A (1985-1990); GPC was 24.6% and GNB was 75.4% in Group B (1995-2000). The predominant bacteria were in the following order: Preudomonas (21.9%), pneumococcal (18.8%), streptococcus (10.9%), acinetobacter (9.4%), staphylococcus epidermidis (7.8%), and klebsiella (7.8%) in Group A; and preudomonas (30.7%), acinetobacter (12.3%), staphylococcus epidermidis (12.3%), klebsiella (10.5%), enteric bacilli (7.0%), and staphylococcus aureus (7.0%) in Group B. The results suggest that GNB is the main pathogen in recent years; sensibility of most drugs in the 1990s fell in varying degrees compared with that in the 1980s, but antibacterial in common use is still available.