We report results of a study of doubly charmed baryons and charmed strange baryons. The analysis is performed using a 980 fb(-1) data sample collected with the Belle detector at the KEKB asymmetric-energy e(+)e(-) collider. We search for doubly charmed baryons Xi(+(+))(cc) with the Lambda(+)(c) K- pi(+)(pi(+) ) and. Xi(0)(c) pi(+)(pi(+)) final states. No significant signal is observed. We also search for two excited charmed strange baryons, Xi(c)(3055)(+) and Xi(c)(3123)(+) with the Sigma(++)(c)(2455)K- and Sigma(++)(c)(2520)K- final states. The Xi(c)(3055)(+) signal is observed with a significance of 6.6 standard deviations including systematic uncertainty, while no signature of the Xi(c)(3123)(+) is seen. We also study properties of the Xi(c)(2645)(+) and measure a width of 2.6 +/- 0.2(stat) +/- 0.4(syst) MeV/c(2), which is the first significant determination.