The objective of this study was to examine the effect of 2 varieties (Minica and Primo) and pelleting temperature (untreated, 60°C, and 84°C) of fava bean (FB) on in situ ruminal degradation of CP. For this purpose, 4 rumen cannulated dairy cows were used in a completely randomized block design with a 2 × 3 factorial arrangement of treatments. Samples of FB were ground (2-mm), weighed (5-g) in triplicate in polyester bags, and incubated in the rumen for 0, 2, 4, 8, 16, 24, 48 and 72h. Ruminal degradation kinetic parameters of CP were determined using a nonlinear model: P = a + b (1 − e^{−c(t− L)}), where P = disappearance at incubation time t (h), a = soluble and rapidly degradable fraction (%), b = slowly degradable fraction (%), c (/h) = fractional rate of disappearance of the fraction b, and L = lag time (h). Effective rumen degradability (ERD) was calculated as: a + [bc/(c + k_p)] × e(^−kpL) with k_p = ruminal fractional passage rate of 6.1%/h. Data were analyzed using the MIXED procedure (SAS) with variety, pelleting temperature and variety × pelleting temperature interaction as fixed effects while cow was a random effect. Significance was declared when P ≤ 0.05. Compared with untreated treatment, pelleting FB (Minica and Primo) at 60°C increased (+26%) the soluble fraction (a), while the extent of increase was higher for Primo than for Minica (+17 vs. + 9%) when pelleted at 84°C (interaction variety × pelleting temperature; P = 0.01). The fraction (b) was similar between the 2 varieties and was lower (P < 0.01) for the FB pelleted at 60°C (20%) and 84°C (27%) than for the untreated FB (36%). The rate of disappearance (c) of the fraction (b) was unaffected by experimental treatments. An increase (P < 0.01) in ERD of CP was observed when FB (Minica and Primo) were treated at 60°C and 84°C, but the magnitude of increase was higher for Minica (+14%) than for Primo (+8%) when treated at 60°C (interaction variety × pelleting temperature; P = 0.03). We conclude that pelleting FB at 60°C and 84°C increased CP solubility and consequently, enhanced ERD of CP. The extent of the effect of pelleting temperature on CP degradability varied with the variety of FB used.