配置文件改成这样

server {
        listen  80;  
		server_name sub.domain.com;  
		set $root_path '/srv/www/default';  
		root $root_path;  
	  
		index index.php index.html index.htm;  
	  
		try_files $uri $uri/ @rewrite;  
	  
		location @rewrite {  
			rewrite ^/(.*)$ /index.php?_url=/$1;  
		}  
	  
		location ~ \.php {  
	  
			fastcgi_pass 127.0.0.1:9000;  
			fastcgi_index /index.php;  
	  
			fastcgi_split_path_info       ^(.+\.php)(/.+)$;  
			fastcgi_param PATH_INFO       $fastcgi_path_info;  
			fastcgi_param PATH_TRANSLATED $document_root$fastcgi_path_info;  
			fastcgi_param SCRIPT_FILENAME $document_root$fastcgi_script_name;  
			include                       fastcgi_params;
		}  
	  
		location ~* ^/(css|img|js|flv|swf|download)/(.+)$ {  
			root $root_path;  
		}  
	  
		location ~ /\.ht {  
			deny all;  
		}  
    }

在CentOS7.1+Nginx1.8.0+Laravel5.0测试通过