A straddled vehicle comprising: a body frame ; a rear wheel ; and a unit-swing type engine supported at the body frame to be swingable in a vehicle top-and-bottom direction (V) together with the rear wheel , wherein the unit-swing type engine includes a crankcase that stores a crankshaft (CS) in a crank chamber (CR), a scavenge pump (SP) for collecting oil (OL) in the crank chamber (CR) such that an inside of the crank chamber (CR) of the crankcase has a negative pressure, and a feed pump (FP) for supplying the oil (OL) collected by the scavenge pump (SP) to the crankshaft (CS), the scavenge pump (SP) and the feed pump (FP) are arranged in the crankcase , the rear wheel is provided at a position further rearward than the crankshaft (CS) in a vehicle front-and-rear direction (L), the crankcase includes a flow path forming portion that forms an oil flow path for leading the oil (OL) discharged from an oil discharge port of the scavenge pump (SP) to an oil inlet port of the feed pump (FP), the flow path forming portion includes a partition wall that sections a space located at a position further downward than the crankshaft (CS) into a first flow path space and a second flow path space and is provided at a position further downward than the crankshaft (CS), the partition wall is formed such that the first flow path space and the second flow path space are arranged in a vehicle width direction (H), at least one communication hole that form part of the oil flow path is provided in the partition wall , a first guide flow path for guiding oil (OL) in the crank chamber (CR) to an oil inlet port of the scavenge pump (SP) is provided in the flow path forming portion and the first guide flow path is formed such that the size of the cross section of the first guide flow path is gradually reduced from an upstream position to a downstream position. a body frame ; a rear wheel ; and a unit-swing type engine supported at the body frame to be swingable in a vehicle top-and-bottom direction (V) together with the rear wheel , wherein the unit-swing type engine includes a crankcase that stores a crankshaft (CS) in a crank chamber (CR), a scavenge pump (SP) for collecting oil (OL) in the crank chamber (CR) such that an inside of the crank chamber (CR) of the crankcase has a negative pressure, and a feed pump (FP) for supplying the oil (OL) collected by the scavenge pump (SP) to the crankshaft (CS), the scavenge pump (SP) and the feed pump (FP) are arranged in the crankcase , the rear wheel is provided at a position further rearward than the crankshaft (CS) in a vehicle front-and-rear direction (L), the crankcase includes a flow path forming portion that forms an oil flow path for leading the oil (OL) discharged from an oil discharge port of the scavenge pump (SP) to an oil inlet port of the feed pump (FP), the flow path forming portion includes a partition wall that sections a space located at a position further downward than the crankshaft (CS) into a first flow path space and a second flow path space and is provided at a position further downward than the crankshaft (CS), the partition wall is formed such that the first flow path space and the second flow path space are arranged in a vehicle width direction (H), at least one communication hole that form part of the oil flow path is provided in the partition wall , a first guide flow path for guiding oil (OL) in the crank chamber (CR) to an oil inlet port of the scavenge pump (SP) is provided in the flow path forming portion and the first guide flow path is formed such that the size of the cross section of the first guide flow path is gradually reduced from an upstream position to a downstream position. <EOS>